Financing Receivables - Components (Details) - Sunlight - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020	Jun. 30, 2020
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amounts outstanding	$ 46,578	$ 41,752
Unamortized discount	(781)	(893)
Allowance for credit losses	(322)	(246)
Carrying value	$ 45,475	40,613
Participation interest in loan pool	5.00%
Advances
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amounts outstanding	$ 40,979	35,401
Allowance for credit losses	(211)	(121)
Carrying value	40,768	35,280
Loans and Loan Participation
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amounts outstanding	5,599	6,351
Unamortized discount	(781)	(893)
Allowance for credit losses	(111)	(125)
Carrying value	4,707	5,333
Residential solar loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amounts outstanding	$ 5,300	$ 6,000
Participation interest in loan pool	5.00%	5.00%	5.00%
Indirect Channel Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Amounts outstanding	$ 300	$ 400

Financing Receivable, Participation Interest In Loan Pool

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- Definition

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+ References

No definition available.

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- Definition

Amount excluding accrued interest, of allowance for credit loss on financing receivable, classified as noncurrent.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=124255206&loc=SL82895884-210446

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- Definition

Amount, before allowance for credit loss, fee, and loan in process, of financing receivable. Excludes financing receivable covered under loss sharing agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (b)
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
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Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(7))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

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- Definition

Amount excluding accrued interest, after allowance for credit loss, of financing receivable classified as noncurrent.

+ References

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- Definition

Amount of unamortized loan commitment, origination, and other fees (costs) and purchase premium (discount) on financing receivable. Excludes financing receivable covered under loss sharing agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=123577603&loc=d3e5074-111524

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-Publisher FASB
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-URI http://asc.fasb.org/extlink&oid=6378536&loc=d3e10092-111533

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