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Restatement of Previously Issued Financial Statements - Balance Sheet (Details) - USD ($) | Mar. 31, 2021 | Dec. 31, 2020 | Sep. 30, 2020 | Aug. 26, 2020 | Mar. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
--- | --- | --- | --- | --- | --- | --- | ---
Balance Sheet |  |  |  |  |  |  |
Total assets | $ 212,390,000 | $ 205,850,000 |  |  |  | $ 188,047,000 |
Liabilities and stockholders' equity |  |  |  |  |  |  |
Total current liabilities | 208,250,000 | 190,515,000 |  |  |  | 109,348,000 |
Total liabilities | 467,044,000 | 383,259,000 |  |  |  | 212,579,000 |
Convertible preferred stock, $0.00001 par value; 409,351,021 and 321,346,716 shares authorized as of December 31, 2020 and 2019, respectively; 175,437,783 and 191,139,933 shares issued and outstanding as of December 31, 2020 and 2019, respectively; (liquidation preference of $257,947 and $258,041 as of December 31, 2020 and 2019, respectively) | 220,955,000 | 220,563,000 |  |  |  | 231,129,000 | $ 218,931,000
Stockholders' equity |  |  |  |  |  |  |
Series 1 convertible preferred stock, $0.00001 par value; 4,305 shares authorized as of December 31, 2020 and 2019; 2,961 shares issued and outstanding as of December 31, 2020 and 2019 | 0 | 0 |  |  |  |  |
Common stock | 0 | 0 |  |  |  |  |
Additional paid-in capital | 14,726,000 | 10,061,000 |  |  |  | 3,339,000 |
Accumulated deficit | (490,394,000) | (407,841,000) |  |  |  | (259,054,000) |
Total stockholders' deficit | (475,609,000) | (397,972,000) |  |  | $ (264,867,000) | (255,661,000) | (210,041,000)
Total liabilities, convertible preferred stock and stockholders' deficit | 212,390,000 | 205,850,000 |  |  |  | 188,047,000 |
Star Peak Energy Transition Corp [Member] |  |  |  |  |  |  |
Balance Sheet |  |  |  |  |  |  |
Total assets | 384,598,056 | 385,286,084 | $ 386,179,543 |  |  | 253,018 |
Liabilities and stockholders' equity |  |  |  |  |  |  |
Total current liabilities | 2,686,624 | 2,809,435 | 716,028 |  |  | 246,568 |
Deferred legal fees | 203,910 | 203,910 | 203,910 |  |  |  |
Deferred underwriting commissions | 13,425,476 | 13,425,476 | 13,425,476 | $ 12,300,000 |  |  |
Convertible preferred stock warrant liabilities | 276,873,719 | 121,091,978 | 11,822,148 |  |  |  |
Total liabilities | 293,189,729 | 137,530,799 | 26,167,562 |  |  | 246,568 |
Convertible preferred stock, $0.00001 par value; 409,351,021 and 321,346,716 shares authorized as of December 31, 2020 and 2019, respectively; 175,437,783 and 191,139,933 shares issued and outstanding as of December 31, 2020 and 2019, respectively; (liquidation preference of $257,947 and $258,041 as of December 31, 2020 and 2019, respectively) | 86,408,320 | 242,755,280 | 355,011,980 |  |  |  |
Stockholders' equity |  |  |  |  |  |  |
Series 1 convertible preferred stock, $0.00001 par value; 4,305 shares authorized as of December 31, 2020 and 2019; 2,961 shares issued and outstanding as of December 31, 2020 and 2019 |  |  |  |  |  |  |
Additional paid-in capital | 273,994,882 | 117,649,486 | 5,393,908 |  |  | 23,994 |
Accumulated deficit | (268,998,806) | (112,651,848) | (395,152) |  |  | (18,550) |
Total stockholders' deficit | 5,000,007 | 5,000,005 | 5,000,001 |  | 5,350 | 6,450 | 16,856
Total liabilities, convertible preferred stock and stockholders' deficit | 384,598,056 | 385,286,084 | 386,179,543 |  |  | 253,018 |
Star Peak Energy Transition Corp [Member] | As Previously Reported |  |  |  |  |  |  |
Balance Sheet |  |  |  |  |  |  |
Total assets |  |  | 386,179,543 |  |  |  |
Liabilities and stockholders' equity |  |  |  |  |  |  |
Total current liabilities |  |  | 716,028 |  |  |  |
Deferred legal fees |  |  | 203,910 |  |  |  |
Deferred underwriting commissions |  |  | 13,425,476 |  |  |  |
Total liabilities |  |  | 14,345,414 |  |  |  |
Convertible preferred stock, $0.00001 par value; 409,351,021 and 321,346,716 shares authorized as of December 31, 2020 and 2019, respectively; 175,437,783 and 191,139,933 shares issued and outstanding as of December 31, 2020 and 2019, respectively; (liquidation preference of $257,947 and $258,041 as of December 31, 2020 and 2019, respectively) |  |  | 366,834,120 |  |  |  |
Stockholders' equity |  |  |  |  |  |  |
Additional paid-in capital |  |  | 5,394,034 |  |  |  |
Accumulated deficit |  |  | (395,152) |  |  |  |
Total stockholders' deficit |  |  | 5,000,009 |  |  |  |
Total liabilities, convertible preferred stock and stockholders' deficit |  |  | 386,179,543 |  |  |  |
Star Peak Energy Transition Corp [Member] | Restatement Adjustment |  |  |  |  |  |  |
Liabilities and stockholders' equity |  |  |  |  |  |  |
Convertible preferred stock warrant liabilities |  |  | 11,822,148 |  |  |  |
Total liabilities |  |  | 11,822,148 |  |  |  |
Convertible preferred stock, $0.00001 par value; 409,351,021 and 321,346,716 shares authorized as of December 31, 2020 and 2019, respectively; 175,437,783 and 191,139,933 shares issued and outstanding as of December 31, 2020 and 2019, respectively; (liquidation preference of $257,947 and $258,041 as of December 31, 2020 and 2019, respectively) |  |  | (11,822,140) |  |  |  |
Stockholders' equity |  |  |  |  |  |  |
Additional paid-in capital |  |  | (126) |  |  |  |
Total stockholders' deficit |  |  | (8) |  |  |  |
Star Peak Energy Transition Corp [Member] | Restatement of warrants as derivative liabilities |  |  |  |  |  |  |
Balance Sheet |  |  |  |  |  |  |
Total assets |  |  | 386,179,543 |  |  |  |
Liabilities and stockholders' equity |  |  |  |  |  |  |
Total current liabilities |  |  | 716,028 |  |  |  |
Deferred legal fees |  |  | 203,910 |  |  |  |
Deferred underwriting commissions |  |  | 13,425,476 |  |  |  |
Convertible preferred stock warrant liabilities |  |  | 11,822,148 |  |  |  |
Total liabilities |  |  | 26,167,562 |  |  |  |
Convertible preferred stock, $0.00001 par value; 409,351,021 and 321,346,716 shares authorized as of December 31, 2020 and 2019, respectively; 175,437,783 and 191,139,933 shares issued and outstanding as of December 31, 2020 and 2019, respectively; (liquidation preference of $257,947 and $258,041 as of December 31, 2020 and 2019, respectively) |  |  | 355,011,980 |  |  |  |
Stockholders' equity |  |  |  |  |  |  |
Additional paid-in capital |  |  | 5,393,908 |  |  |  |
Accumulated deficit |  |  | (395,152) |  |  |  |
Total stockholders' deficit |  |  | 5,000,001 |  |  |  |
Total liabilities, convertible preferred stock and stockholders' deficit |  |  | 386,179,543 |  |  |  |
Star Peak Energy Transition Corp [Member] | Restatement of warrants as derivative liabilities | As Previously Reported |  |  |  |  |  |  |
Balance Sheet |  |  |  |  |  |  |
Total assets |  | 385,286,084 | 386,179,543 |  |  |  |
Liabilities and stockholders' equity |  |  |  |  |  |  |
Total current liabilities |  | 2,809,435 | 716,028 |  |  |  |
Deferred legal fees |  | 203,910 | 203,910 |  |  |  |
Deferred underwriting commissions |  | 13,425,476 | 13,425,476 |  |  |  |
Total liabilities |  | 16,438,821 | 14,345,414 |  |  |  |
Convertible preferred stock, $0.00001 par value; 409,351,021 and 321,346,716 shares authorized as of December 31, 2020 and 2019, respectively; 175,437,783 and 191,139,933 shares issued and outstanding as of December 31, 2020 and 2019, respectively; (liquidation preference of $257,947 and $258,041 as of December 31, 2020 and 2019, respectively) |  | 363,847,260 | 366,834,120 |  |  |  |
Stockholders' equity |  |  |  |  |  |  |
Additional paid-in capital |  | 8,380,865 | 5,394,034 |  |  |  |
Accumulated deficit |  | (3,382,018) | (395,152) |  |  |  |
Total stockholders' deficit |  | 5,000,003 | 5,000,009 |  |  |  |
Total liabilities, convertible preferred stock and stockholders' deficit |  | 385,286,084 | 386,179,543 |  |  |  |
Star Peak Energy Transition Corp [Member] | Restatement of warrants as derivative liabilities | Restatement Adjustment |  |  |  |  |  |  |
Liabilities and stockholders' equity |  |  |  |  |  |  |
Convertible preferred stock warrant liabilities |  | 121,091,978 | 11,822,148 |  |  |  |
Total liabilities |  | 121,091,978 | 11,822,148 |  |  |  |
Convertible preferred stock, $0.00001 par value; 409,351,021 and 321,346,716 shares authorized as of December 31, 2020 and 2019, respectively; 175,437,783 and 191,139,933 shares issued and outstanding as of December 31, 2020 and 2019, respectively; (liquidation preference of $257,947 and $258,041 as of December 31, 2020 and 2019, respectively) |  | (121,091,980) | (11,822,140) |  |  |  |
Stockholders' equity |  |  |  |  |  |  |
Additional paid-in capital |  | 109,268,621 | (126) |  |  |  |
Accumulated deficit |  | (109,269,830) |  |  |  |  |
Total stockholders' deficit |  | 2 | (8) |  |  |  |
Star Peak Energy Transition Corp [Member] | Class A common stock |  |  |  |  |  |  |
Stockholders' equity |  |  |  |  |  |  |
Common stock |  | 1,408 |  |  |  |  |
Star Peak Energy Transition Corp [Member] | Class A common stock | Restatement of warrants as derivative liabilities |  |  |  |  |  |  |
Stockholders' equity |  |  |  |  |  |  |
Common stock |  |  | 286 |  |  |  |
Star Peak Energy Transition Corp [Member] | Class A common stock | Restatement of warrants as derivative liabilities | As Previously Reported |  |  |  |  |  |  |
Stockholders' equity |  |  |  |  |  |  |
Common stock |  | 197 | 168 |  |  |  |
Star Peak Energy Transition Corp [Member] | Class A common stock | Restatement of warrants as derivative liabilities | Restatement Adjustment |  |  |  |  |  |  |
Stockholders' equity |  |  |  |  |  |  |
Common stock |  | 1,211 | 118 |  |  |  |
Star Peak Energy Transition Corp [Member] | Common Class B |  |  |  |  |  |  |
Stockholders' equity |  |  |  |  |  |  |
Common stock | 959 | 959 | 959 |  |  | 1,006 |
Total stockholders' deficit | $ 959 | 959 |  |  | $ 1,006 | $ 1,006 | $ 1,006
Star Peak Energy Transition Corp [Member] | Common Class B | As Previously Reported |  |  |  |  |  |  |
Stockholders' equity |  |  |  |  |  |  |
Common stock |  |  | 959 |  |  |  |
Star Peak Energy Transition Corp [Member] | Common Class B | Restatement of warrants as derivative liabilities |  |  |  |  |  |  |
Stockholders' equity |  |  |  |  |  |  |
Common stock |  |  | 959 |  |  |  |
Star Peak Energy Transition Corp [Member] | Common Class B | Restatement of warrants as derivative liabilities | As Previously Reported |  |  |  |  |  |  |
Stockholders' equity |  |  |  |  |  |  |
Common stock |  | $ 959 | $ 959 |  |  |  |

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