Stockholders' Equity	12 Months Ended
Stockholders' Equity	Dec. 31, 2020
Equity [Abstract]
Stockholders' Equity	Stockholders' Equity Series A and Series C Convertible Preferred Stock The Series A and Series C convertible preferred stock was convertible into our Series A common stock at an initial conversion ratio of 1:1, subject to appropriate adjustment in the event of any stock dividend, stock split, combination or other similar recapitalization with respect to any of our common stock and to broad-based weighted average anti-dilution protection. The Series A and Series C convertible preferred stock was mandatorily convertible into our Series A common stock upon either (a) the closing of a public offering of shares of our common stock with aggregate gross proceeds, net of underwriting discounts and commissions, of not less than $175.0 million at a per share offering price of at least 1.25 times the original purchase price of our Series A convertible preferred stock or (b) the affirmative vote of at least 80% of the shares of Series A and Series C convertible preferred stock voting as a single class and on an "as converted basis". The holders of Series A and Series C convertible preferred stock were entitled to cast the number of votes equal to the number of whole shares of Series A common stock into which the Series A and Series C convertible preferred stock held by such holders is convertible as of the record date for determining stockholders entitled to vote on such matter. In March 2018, we increased the number of authorized voting shares of our convertible preferred stock to 64,294,899 shares, of which 47,149,592 shares were designated as Series A convertible preferred stock and 17,145,306 shares were designated as Series C convertible preferred stock. During the year ended December 31, 2018, we issued 13,006,780 shares of Series C convertible preferred stock at $13.53 per share in exchange for $176.0 million in cash. In connection with our IPO, we converted 46,351,877 shares of our Series A convertible preferred stock and 14,127,140 shares of our Series C convertible preferred stock, which represented all the outstanding shares of our Series A convertible preferred stock and Series C convertible preferred stock, into 60,479,017 shares of our common stock. Series B Convertible Preferred Stock The Series B convertible preferred stock was convertible into our Series A common stock at a rate determined by dividing the original issue price by the conversion price of $8.70 at or after the earlier of (a) November 9, 2018 or (b) immediately prior to the consummation of a sale of Sunnova, subject to appropriate adjustment in the event of any stock dividend, stock split, combination or other similar recapitalization with respect to any of our common stock and to broad-based weighted average anti-dilution protection. The Series B convertible preferred stock was mandatorily convertible into our Series A common stock upon either (a) the closing of the sale of shares of any of our common stock to the public at a price of at least approximately $6.6558 per share (subject to appropriate adjustments) or (b) the affirmative vote of at least 75% of the shares of Series A and Series B convertible preferred stock. Each holder of Series B convertible preferred stock was entitled to cast the number of votes equal to the number of whole shares of Series A common stock into which the Series B convertible preferred stock held by such holder were convertible as of the record date for determining stockholders entitled to vote on such matter. In January 2018, we issued 13,013 shares of Series B convertible preferred stock at $8.70 per share in exchange for $113,000 in cash. In March 2018, we exchanged all outstanding shares of Series B convertible preferred stock, plus accrued paid-in-kind interest thereon, for 4,763,086 shares of Series A convertible preferred stock. Immediately following the exchange, we canceled all shares of Series B convertible preferred stock. As of December 31, 2018, there was no Series B convertible preferred stock outstanding. Series A Common Stock In March 2018, we increased the number of authorized voting shares of Series A common stock to 77,153,879 shares, of which 64,294,899 shares were reserved for the issuance of Series A common stock upon the conversion of Series A or Series C convertible preferred stock. In connection with our IPO, our Series A common stock was redesignated as common stock. Series B Common Stock Our Series B non-voting common stock related to our equity-based compensation plans (see Note 14, Equity-Based Compensation). In connection with our IPO, we converted 23,870 shares of our non-voting Series B common stock, which represented all the outstanding shares of our Series B common stock, into 23,870 shares of our voting Series A common stock, which was subsequently redesignated as common stock. Common Stock On July 24, 2019, we priced 14,000,000 shares of common stock in our IPO at a public offering price of $12.00 per share and on July 25, 2019 our common stock began trading on the New York Stock Exchange under the symbol "NOVA". On August 19, 2019, we issued and sold an additional 865,267 shares of our common stock at a public offering price of $12.00 per share pursuant to the underwriters' exercise of their option to purchase additional shares. We received aggregate net proceeds from our IPO of approximately $162.3 million, after deducting underwriting discounts and commissions of approximately $10.7 million and offering expenses of approximately $5.4 million. We used the proceeds from our IPO to repay indebtedness and for working capital purposes. In December 2020, we sold 4,025,000 shares of common stock at a public offering price of $37.00 per share. We received aggregate net proceeds of approximately $142.7 million, after deducting underwriting discounts and commissions of approximately $6.0 million and offering expenses of approximately $300,000. We used the net proceeds from the offering to acquire solar equipment, repay indebtedness and for working capital purposes. During the year ended December 31, 2020, certain of the holders of our 9.75% convertible senior notes converted approximately $150.8 million aggregate principal amount, including accrued and unpaid interest to the date of each conversion, of our 9.75% convertible senior notes into 11,168,874 shares of our common stock. Such conversions resulted in a loss on extinguishment of debt under GAAP of $142.8 million for the year ended December 31, 2020. See Note 17, Subsequent Events.