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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

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