Commitment and Contingencies (Details) - Obligation to Repurchase Loans - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Loss Contingencies [Line Items]
Loan purchase obligation	$ 111.3	$ 39.3
Maximum estimate of potential loss	$ 12,905.5	$ 5,180.7

Reflects the estimated amount of loss from the specified contingency as of the balance sheet date.

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-Name Accounting Standards Codification
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-Publisher FASB
-Name Accounting Standards Codification
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Name:	us-gaap_LossContingencyEstimateOfPossibleLoss
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant