Parent Company Financials. (Tables)
   | 
6 Months Ended | 
Jun. 30, 2021  | 
| Condensed Financial Information Disclosure [Abstract] | 
 
 | 
| Schedule of parent company financial statements | 
  
    |   | 
  | 
    June
    30,  2021 | 
  | 
  | 
    December 31,  2020 | 
  | 
 
  
    | ASSETS | 
  | 
      | 
  | 
  | 
      | 
  | 
 
  
    | Current Assets: | 
  | 
      | 
  | 
  | 
      | 
  | 
 
  
    | Cash and cash equivalents | 
  | 
    $ | 
15,128 | 
  | 
  | 
    $ | 
25,632 | 
  | 
 
  
    | Receivables from subsidiaries | 
  | 
      | 
13,460 | 
  | 
  | 
      | 
15,548 | 
  | 
 
  
    | Other current assets | 
  | 
      | 
2,588 | 
  | 
  | 
      | 
1,836 | 
  | 
 
  
    | Total current assets | 
  | 
      | 
31,176 | 
  | 
  | 
      | 
43,016 | 
  | 
 
  
    |   | 
  | 
      | 
  | 
  | 
  | 
      | 
  | 
  | 
 
  
    | Property and equipment, net | 
  | 
      | 
108 | 
  | 
  | 
      | 
142 | 
  | 
 
  
    | Other Assets: | 
  | 
      | 
  | 
  | 
  | 
      | 
  | 
  | 
 
  
    | Investments in subsidiaries | 
  | 
      | 
264,645 | 
  | 
  | 
      | 
246,518 | 
  | 
 
  
    | Alto West, LLC receivable | 
  | 
      | 
27,592 | 
  | 
  | 
      | 
42,649 | 
  | 
 
  
    | Right of use operating lease assets, net | 
  | 
      | 
2,844 | 
  | 
  | 
      | 
2,985 | 
  | 
 
  
    | Other assets | 
  | 
      | 
796 | 
  | 
  | 
      | 
1,088 | 
  | 
 
  
    | Total other assets | 
  | 
      | 
295,877 | 
  | 
  | 
      | 
293,240 | 
  | 
 
  
    | Total Assets | 
  | 
    $ | 
327,161 | 
  | 
  | 
    $ | 
336,398 | 
  | 
 
  
    | Current Liabilities: | 
  | 
      | 
  | 
  | 
  | 
      | 
  | 
  | 
 
  
    | Accounts payable and accrued liabilities | 
  | 
    $ | 
5,439 | 
  | 
  | 
    $ | 
2,001 | 
  | 
 
  
    | Accrued Alto Op Co. purchase | 
  | 
      | 
3,829 | 
  | 
  | 
      | 
3,829 | 
  | 
 
  
    | Current portion of long-term debt | 
  | 
      | 
6,696 | 
  | 
  | 
      | 
25,533 | 
  | 
 
  
    | Other current liabilities | 
  | 
      | 
329 | 
  | 
  | 
      | 
473 | 
  | 
 
  
    | Total current liabilities | 
  | 
      | 
16,293 | 
  | 
  | 
      | 
31,836 | 
  | 
 
  
    |   | 
  | 
      | 
  | 
  | 
  | 
      | 
  | 
  | 
 
  
    | Long-term debt, net of current portion | 
  | 
      | 
—  | 
  | 
  | 
      | 
5,564 | 
  | 
 
  
    | Other liabilities | 
  | 
      | 
2,849 | 
  | 
  | 
      | 
2,763 | 
  | 
 
  
    | Total Liabilities | 
  | 
      | 
19,142 | 
  | 
  | 
      | 
40,163 | 
  | 
 
  
    | Stockholders’ Equity: | 
  | 
      | 
  | 
  | 
  | 
      | 
  | 
  | 
 
  
    | Preferred stock | 
  | 
      | 
1 | 
  | 
  | 
      | 
1 | 
  | 
 
  
    | Common and non-voting common stock | 
  | 
      | 
73 | 
  | 
  | 
      | 
72 | 
  | 
 
  
    | Additional paid-in capital | 
  | 
      | 
1,035,980 | 
  | 
  | 
      | 
1,036,638 | 
  | 
 
  
    | Accumulated other comprehensive loss | 
  | 
      | 
(3,878 | 
) | 
  | 
      | 
(3,878 | 
) | 
 
  
    | Accumulated deficit | 
  | 
      | 
(724,157 | 
) | 
  | 
      | 
(736,598 | 
) | 
 
  
    | Total Alto Ingredients, Inc. stockholders’ equity | 
  | 
      | 
308,019 | 
  | 
  | 
      | 
296,235 | 
  | 
 
  
    | Total Liabilities and Stockholders’ Equity | 
  | 
    $ | 
327,161 | 
  | 
  | 
    $ | 
336,398 | 
  | 
 
   
   
 | 
| Schedule of statement of operations parent company | 
  
    |   | 
  | 
    Three
    Months Ended  June 30, | 
  | 
  | 
    Six
    Months Ended  June 30, | 
  | 
 
  
    |   | 
  | 
    2021 | 
  | 
  | 
    2020 | 
  | 
  | 
    2021 | 
  | 
  | 
    2020 | 
  | 
 
  
    |   | 
  | 
      | 
  | 
  | 
      | 
  | 
  | 
      | 
  | 
  | 
      | 
  | 
 
  
    | Management fees from subsidiaries | 
  | 
    $ | 
2,486 | 
  | 
  | 
    $ | 
2,873 | 
  | 
  | 
    $ | 
5,012 | 
  | 
  | 
    $ | 
6,126 | 
  | 
 
  
    | Selling, general and administrative expenses | 
  | 
      | 
4,393 | 
  | 
  | 
      | 
4,308 | 
  | 
  | 
      | 
9,044 | 
  | 
  | 
      | 
9,685 | 
  | 
 
  
    | Income (loss) from operations | 
  | 
      | 
(1,907 | 
) | 
  | 
      | 
(1,435 | 
) | 
  | 
      | 
(4,032 | 
) | 
  | 
      | 
(3,559 | 
) | 
 
  
    | Fair value adjustments | 
  | 
      | 
—  | 
  | 
  | 
      | 
(1,314 | 
) | 
  | 
      | 
—  | 
  | 
  | 
      | 
(641 | 
) | 
 
  
    | Interest expense, net | 
  | 
      | 
(704 | 
) | 
  | 
      | 
(1,721 | 
) | 
  | 
      | 
(1,731 | 
) | 
  | 
      | 
(3,297 | 
) | 
 
  
    | Other income (expense) | 
  | 
      | 
410 | 
  | 
  | 
      | 
(140 | 
) | 
  | 
      | 
1,218 | 
  | 
  | 
      | 
(162 | 
) | 
 
  
    | Loss before benefit for income taxes | 
  | 
      | 
(2,201 | 
) | 
  | 
      | 
(4,610 | 
) | 
  | 
      | 
(4,545 | 
) | 
  | 
      | 
(7,659 | 
) | 
 
  
    | Benefit for income taxes | 
  | 
      | 
—  | 
  | 
  | 
      | 
—  | 
  | 
  | 
      | 
—  | 
  | 
  | 
      | 
—  | 
  | 
 
  
    | Net loss | 
  | 
      | 
(2,201 | 
) | 
  | 
      | 
(4,610 | 
) | 
  | 
      | 
(4,545 | 
) | 
  | 
      | 
(7,659 | 
) | 
 
  
    | Equity in income (losses) of subsidiaries | 
  | 
      | 
10,591 | 
  | 
  | 
      | 
19,574 | 
  | 
  | 
      | 
17,613 | 
  | 
  | 
      | 
(2,477 | 
) | 
 
  
    | Net income (loss) attributed to Alto Ingredients, Inc. | 
  | 
    $ | 
8,390 | 
  | 
  | 
    $ | 
14,964 | 
  | 
  | 
    $ | 
13,068 | 
  | 
  | 
    $ | 
(10,136 | 
) | 
 
   
  
 | 
| Schedule of statement of cash flows parent company | 
  
    |   | 
  | 
    For
    the Six Months Ended  
June 30, | 
  | 
 
  
    |   | 
  | 
    2021 | 
  | 
  | 
    2020 | 
  | 
 
  
    | Operating Activities: | 
  | 
      | 
  | 
  | 
      | 
  | 
 
  
    | Net income (loss) | 
  | 
    $ | 
13,068 | 
  | 
  | 
    $ | 
(10,136 | 
) | 
 
  
    | Adjustments to reconcile net income (loss) to cash used in operating activities: | 
  | 
      | 
  | 
  | 
  | 
      | 
  | 
  | 
 
  
    | Equity in (income) losses of subsidiaries | 
  | 
      | 
(17,613 | 
) | 
  | 
      | 
2,477 | 
  | 
 
  
    | Fair value adjustments | 
  | 
      | 
—  | 
  | 
  | 
      | 
(641 | 
) | 
 
  
    | Depreciation | 
  | 
      | 
33 | 
  | 
  | 
      | 
67 | 
  | 
 
  
    | Amortization of debt (premiums) discounts | 
  | 
      | 
409 | 
  | 
  | 
      | 
(115 | 
) | 
 
  
    | Changes in operating assets and liabilities: | 
  | 
      | 
  | 
  | 
  | 
      | 
  | 
  | 
 
  
    | Accounts receivable | 
  | 
      | 
2,088 | 
  | 
  | 
      | 
(1,207 | 
) | 
 
  
    | Other assets | 
  | 
      | 
(319 | 
) | 
  | 
      | 
714 | 
  | 
 
  
    | Accounts payable and accrued expenses | 
  | 
      | 
(2,416 | 
) | 
  | 
      | 
—  | 
  | 
 
  
    | Accounts payable with subsidiaries | 
  | 
      | 
37 | 
  | 
  | 
      | 
475 | 
  | 
 
  
    | Net cash used in operating activities | 
  | 
      | 
(4,713 | 
) | 
  | 
      | 
(8,366 | 
) | 
 
  
    | Investing Activities: | 
  | 
      | 
  | 
  | 
  | 
      | 
  | 
  | 
 
  
    | Additions to property and equipment | 
  | 
      | 
—  | 
  | 
  | 
      | 
—  | 
  | 
 
  
    | Net cash used in investing activities | 
  | 
      | 
—  | 
  | 
  | 
      | 
—  | 
  | 
 
  
    | Financing Activities: | 
  | 
      | 
  | 
  | 
  | 
      | 
  | 
  | 
 
  
    | Proceeds from issuances of common stock | 
  | 
      | 
462 | 
  | 
  | 
      | 
282 | 
  | 
 
  
    | Proceeds from plant receivables | 
  | 
      | 
15,057 | 
  | 
  | 
      | 
5,813 | 
  | 
 
  
    | Proceeds from long-term debt | 
  | 
      | 
—  | 
  | 
  | 
      | 
5,973 | 
  | 
 
  
    | Payments on senior notes | 
  | 
      | 
(24,810 | 
) | 
  | 
      | 
—  | 
  | 
 
  
    | Dividend from subsidiary | 
  | 
      | 
3,500 | 
  | 
  | 
      | 
—  | 
  | 
 
  
    | Net cash provided by (used in) financing activities | 
  | 
      | 
(5,791 | 
) | 
  | 
      | 
12,068 | 
  | 
 
  
    | Net change in cash and cash equivalents | 
  | 
      | 
(10,504 | 
) | 
  | 
      | 
3,702 | 
  | 
 
  
    | Cash and cash equivalents at beginning of period | 
  | 
      | 
25,632 | 
  | 
  | 
      | 
4,985 | 
  | 
 
  
    | Cash and cash equivalents at end of period | 
  | 
    $ | 
15,128 | 
  | 
  | 
    $ | 
8,687 | 
  | 
 
   
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