Summary of Significant Accounting Policies - Deferred Revenue (Details) - USD ($) $ in Thousands |
Sep. 30, 2021 |
Dec. 31, 2020 |
Dec. 31, 2019 |
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Disaggregation of Revenue [Line Items] | |||
Deferred revenue | $ 848,518 | $ 799,276 | $ 729,500 |
Customer agreements | |||
Disaggregation of Revenue [Line Items] | |||
Deferred revenue | 703,144 | 666,741 | |
Customer agreements | Payments received, net | |||
Disaggregation of Revenue [Line Items] | |||
Deferred revenue | 646,269 | 614,906 | |
Customer agreements | Financing component balance | |||
Disaggregation of Revenue [Line Items] | |||
Deferred revenue | 56,875 | 51,835 | |
SREC contracts | |||
Disaggregation of Revenue [Line Items] | |||
Deferred revenue | 145,374 | 132,535 | |
SREC contracts | Payments received, net | |||
Disaggregation of Revenue [Line Items] | |||
Deferred revenue | 138,022 | 126,793 | |
SREC contracts | Financing component balance | |||
Disaggregation of Revenue [Line Items] | |||
Deferred revenue | $ 7,352 | $ 5,742 |
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- Definition Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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