Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022
Operating activities:
Net income	$ 54,955	$ 50,142
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation	686	591
Provision for credit losses	6,867	2,451
Gain on sale of loans	(6,733)	(17,965)
Proceeds from sales of loans	3,356,860	8,214,273
Loans and participations originated and purchased for sale	(3,674,484)	(7,178,991)
Purchases of low-income housing tax credits for sale	(7,932)	(6,651)
Proceeds from sale of low-income housing tax credits	8,670
Change in servicing rights for paydowns and fair value adjustments	4,554	(4,896)
Net change in:
Mortgage loans in process of securitization	(42,880)	244,959
Other assets and receivables	(8,116)	(15,325)
Other liabilities	7,607	8,030
Other	(1,587)	(988)
Net cash (used in) provided by operating activities	(301,533)	1,295,630
Investing activities:
Net change in securities purchased under agreements to resell	26	1,090
Purchases of securities available for sale	(353,249)	(20,002)
Purchases of securities held to maturity	(1,540)
Proceeds from calls, maturities and paydowns of securities available for sale	832	9,302
Proceeds from calls, maturities and paydowns of securities held to maturity	15,783
Purchases of loans	(98,791)	(40,672)	$ (40,700)
Net change in loans receivable	(678,522)	(187,323)
Proceeds from sale of FHLB stock		784
Purchases of premises and equipment	(1,041)	(3,939)
Purchase of servicing rights		(2,057)
Purchase of limited partnership interests	(4,580)	(6,577)
Other investing activities	906	2,245
Net cash used in investing activities	(1,120,176)	(247,149)
Financing activities:
Net change in deposits	1,273,886	(1,506,792)
Proceeds from borrowings	22,335,000	626,000
Repayment of borrowings	(22,185,180)	(780,025)
Proceeds from credit linked notes	153,546
Dividends	(12,126)	(8,757)
Other financing activities	5
Net cash provided by (used in) financing activities	1,565,131	(1,669,574)
Net Change in Cash and Cash Equivalents	143,422	(621,093)
Cash and Cash Equivalents, Beginning of Period	226,164	1,032,614	1,032,614
Cash and Cash Equivalents, End of Period	369,586	411,521	$ 226,164
Supplemental Cash Flows Information:
Interest paid	101,381	10,228
Income taxes paid, net of refunds	966	$ (497)
Transfer of loans from loans receivable to loans held for sale	$ 377,460