Securities Available for Sale - Allowance for Credit Losses (Details) - Asset-backed securities related to Structured Program transactions $ in Thousands	12 Months Ended
Dec. 31, 2021 USD ($)
Debt Securities, Available-for-sale, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	$ (18,736)
Reversal of credit loss expense	3,382
Reversal of allowance arising from PCD financial assets	15,354
Balance at end of period	$ 0

Debt Securities, Available For Sale, Excluding Accrued Interest, Purchased With Credit Deterioration, Reversal Of Allowance For Credit Loss

No definition available.

+ Details

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Namespace Prefix:	lc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtSecuritiesAvailableForSaleAllowanceForCreditLossRollForward
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount excluding accrued interest, of allowance for credit loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479130/326-30-45-1

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount, excluding accrued interest, of increase in allowance for credit loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale) from recovery.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 9
-Subparagraph (h)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479106/326-30-50-9

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: