Loans Receivable and Allowance for Credit Losses - Schedule of Activities in Allowance for loan losses by Portfolio Segments and Unfunded Credit Commitments (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Allowance for unfunded credit reserves
Allowance for unfunded credit commitments, beginning of period			$ 38,000
Allowance for unfunded credit commitments, end of period	$ 39,000		39,000
Provision for credit losses	37,000	$ 26,000	62,000	$ 46,000
Loans transferred from held-for-investment to held-for-sale	139,641	119,550	339,615	280,026
Sales	134,624	123,889	322,791	303,421
Purchases	282,039	117,416	390,119	272,098
Unfunded Credit Commitments
Allowance for unfunded credit reserves
Allowance for unfunded credit commitments, beginning of period	38,544	27,741	37,698	26,264
Provision for credit losses on unfunded credit commitments	238	1,975	1,084	3,455
Foreign currency translation adjustment	1	12	1	9
Allowance for unfunded credit commitments, end of period	38,783	29,728	38,783	29,728
Single-family residential \| Consumer lending
Allowance for unfunded credit reserves
Loans transferred from held-for-investment to held-for-sale	0	0	0	0
Sales	0	0	965	0
Purchases	$ 111,864	$ 79,137	$ 186,600	$ 211,136

Allowance For Unfunded Credit Reserves [Roll Forward]

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Reflects the Allowance for Unfunded Credit Commitments

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Amount, excluding accrued interest, of foreign currency translation gain (loss) which decreases (increases) allowance for credit loss on financing receivable. Excludes net investment in lease.

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Amount of increase in financing receivable from purchase. Excludes net investment in lease.

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Amount of decrease in financing receivable from sale and reclassification to held-for-sale. Excludes net investment in lease.

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Amount of expense (reversal of expense) for expected credit loss for off-balance sheet credit exposure. Excludes off-balance sheet credit exposure accounted for as insurance and instrument accounted for under derivatives and hedging.

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Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value.

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Value of loans and leases held in the entity's portfolio transferred to loans and leases held-for-sale in noncash transactions.

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