Investment Securities (Schedule of Investment Securities) (Details) - USD ($)	Dec. 31, 2022	Dec. 31, 2021
Available-for-sale securities
Amortized Cost	$ 3,769,634,000	$ 2,316,369,000
Gross unrealized gains	511,000	40,094,000
Gross unrealized losses	(527,128,000)	(28,670,000)
Fair Value	3,243,017,000	2,327,793,000
Held-to-maturity securities
Amortized Cost	3,641,055,000	2,942,363,000
Gross unrealized gains	477,000	10,609,000
Gross unrealized losses	(691,711,000)	(52,278,000)
Fair Value	2,949,821,000	2,900,694,000
Less: Allowance for credit losses	(488,000)	(78,000)
Held-to-maturity securities, net of allowance for credit losses	3,640,567,000	2,942,285,000
Equity securities with readily determinable fair value
Amortized Cost	115,552,000	86,989,000
Gross unrealized gains	2,935,000	5,354,000
Gross unrealized losses	(8,122,000)	(1,832,000)
Fair Value	110,365,000	90,511,000
U.S. Treasury
Available-for-sale securities
Amortized Cost	14,943,000	0
Gross unrealized gains	5,000	0
Gross unrealized losses	0	0
Fair Value	14,948,000	0
U.S. government agencies
Available-for-sale securities
Amortized Cost	80,000,000	50,158,000
Gross unrealized gains	36,000	2,349,000
Gross unrealized losses	(5,814,000)	0
Fair Value	74,222,000	52,507,000
Held-to-maturity securities
Amortized Cost	339,614,000	180,192,000
Gross unrealized gains	0	201,000
Gross unrealized losses	(75,293,000)	(3,314,000)
Fair Value	264,321,000	177,079,000
Municipal
Available-for-sale securities
Amortized Cost	173,861,000	161,618,000
Gross unrealized gains	230,000	4,193,000
Gross unrealized losses	(5,436,000)	(217,000)
Fair Value	168,655,000	165,594,000
Held-to-maturity securities
Amortized Cost	179,027,000	187,486,000
Gross unrealized gains	477,000	9,544,000
Gross unrealized losses	(4,066,000)	(223,000)
Fair Value	175,438,000	196,807,000
Corporate notes
Held-to-maturity securities
Amortized Cost	58,232,000	43,955,000
Gross unrealized gains	0	0
Gross unrealized losses	(5,348,000)	(1,119,000)
Fair Value	52,884,000	42,836,000
Financial issuers
Available-for-sale securities
Amortized Cost	93,994,000	96,878,000
Gross unrealized gains	0	418,000
Gross unrealized losses	(9,291,000)	(2,599,000)
Fair Value	84,703,000	94,697,000
Other
Available-for-sale securities
Amortized Cost	1,000,000	1,000,000
Gross unrealized gains	2,000	7,000
Gross unrealized losses	0	0
Fair Value	1,002,000	1,007,000
Mortgage-backed securities
Available-for-sale securities
Amortized Cost	3,308,494,000	1,901,005,000
Gross unrealized gains	238,000	32,830,000
Gross unrealized losses	(488,795,000)	(25,854,000)
Fair Value	2,819,937,000	1,907,981,000
Held-to-maturity securities
Amortized Cost	2,900,031,000	2,530,730,000
Gross unrealized gains	0	864,000
Gross unrealized losses	(583,682,000)	(47,622,000)
Fair Value	2,316,349,000	2,483,972,000
Collateralized mortgage obligations
Available-for-sale securities
Amortized Cost	97,342,000	105,710,000
Gross unrealized gains	0	297,000
Gross unrealized losses	(17,792,000)	0
Fair Value	79,550,000	106,007,000
Held-to-maturity securities
Amortized Cost	164,151,000	0
Gross unrealized gains	0	0
Gross unrealized losses	(23,322,000)	0
Fair Value	140,829,000	0
Mortgage-backed securities, subprime
Available-for-sale securities
Fair Value	$ 0	$ 0