Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022
Operating activities:
Net income	$ 120,257	$ 104,077
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation	1,385	1,204
Provision for credit losses	29,470	8,663
Gain on sale of loans	(18,083)	(39,529)
Proceeds from sales of loans	8,388,537	14,491,319
Loans and participations originated and purchased for sale	(8,900,738)	(13,918,978)
Purchases of low-income housing tax credits for sale	(30,117)	(9,829)
Proceeds from sale of low-income housing tax credits	19,804
Change in servicing rights for paydowns and fair value adjustments	3,257	(9,367)
Net change in:
Mortgage loans in process of securitization	(144,713)	246,193
Other assets and receivables	(37,233)	(17,738)
Other liabilities	28,294	18,389
Other	(3,140)	371
Net cash (used in) provided by operating activities	(543,020)	874,775
Investing activities:
Net change in securities purchased under agreements to resell	52	2,368
Purchases of securities available for sale	(513,520)	(47,866)
Purchases of securities held to maturity	(4,261)
Proceeds from the sale of securities available for sale	132	0
Proceeds from calls, maturities and paydowns of securities available for sale	195,164	12,206
Proceeds from calls, maturities and paydowns of securities held to maturity	61,322
Purchases of loans	(269,855)	(92,533)
Net change in loans receivable	(1,805,415)	(1,199,040)
Purchase of FHLB stock		(10,326)
Proceeds from sale of FHLB stock		784
Purchases of premises and equipment	(2,943)	(5,113)
Purchase of servicing rights		(2,057)
Purchase of limited partnership interests	(71,001)	(13,225)
Proceeds from sale of limited partnership interests	52,458
Other investing activities	1,322	2,924
Net cash used in investing activities	(2,356,545)	(1,351,878)
Financing activities:
Net change in deposits	2,988,519	(682,875)
Proceeds from borrowings	42,149,880	21,595,000
Repayment of borrowings	(42,240,205)	(21,190,050)
Proceeds from notes payable	26,000	2,000
Proceeds from credit linked notes	153,546
Payment of credit linked notes	(2,980)
Repurchase of common stock		(3,935)
Dividends	(24,253)	(17,505)
Other financing activities	204
Net cash provided by (used in) financing activities	3,050,711	(297,365)
Net Change in Cash and Cash Equivalents	151,146	(774,468)
Cash and Cash Equivalents, Beginning of Period	226,164	1,032,614
Cash and Cash Equivalents, End of Period	377,310	258,146
Supplemental Cash Flows Information:
Interest paid	238,521	25,191
Income taxes paid, net of refunds	29,813	$ 28,331
Transfer of loans from loans held for sale to loans receivable	$ 377,460