WAREHOUSE AND OTHER LINES OF CREDIT - Information on Warehouse Borrowings (Details) - Warehouse Agreement Borrowings - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Line of Credit Facility [Line Items]
Maximum outstanding balance during the period	$ 9,078,257	$ 4,622,250	$ 9,180,276	$ 4,622,250
Average balance outstanding during the period	8,515,189	3,633,792	8,066,303	3,433,434
Collateral pledged (loans held for sale)	$ 8,675,750	$ 4,805,413	$ 8,675,750	$ 4,805,413
Weighted average interest rate during the period	2.22%	2.41%	2.25%	2.65%

The average effective interest rate during the reporting period.

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Average amount borrowed under the credit facility during the period.

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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.

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Maximum amount borrowed under the credit facility at any time during the period.

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Carrying amount as of the balance sheet date of loans that have been pledged as collateral for borrowings. If the secured party has the right by contract or custom to sell or re-pledge the collateral, then the debtor reclassifies that asset and report that asset in its statement of financial position separately from other assets not so encumbered.

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