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Investment Securities - Contractual Maturities (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Available for Sale Securities, Amortized Cost
Within one year	$ 209,146	$ 308,474
After one through five years	140,000	71,518
Total, single maturity date	349,146	379,992
Total	1,062,830	1,116,954
Available for Sale Securities, Fair Value
Within one year	207,796	305,406
After one through five years	139,808	71,317
Total, single maturity date	347,604	376,723
Total	1,061,288	1,113,687
Held to Maturity Securities, Amortized Cost
Amortized Cost	1,175,167	1,204,217
Held to Maturity Securities, Fair Value
Fair Value	1,176,178	1,203,535
Mortgage-backed - Agency
Held to Maturity Securities, Amortized Cost
Amortized Cost	11,976	12,016
Held to Maturity Securities, Fair Value
Fair Value	11,108	11,194
Mortgage-backed - Government Agency ("Agency")
Available for Sale Securities, Amortized Cost
Without single maturity date	13,044	14,465
Total	13,044	14,465
Available for Sale Securities, Fair Value
Without single maturity date	13,044	14,467
Total	13,044	14,467
Mortgage-backed - Agency - fair value option
Available for Sale Securities, Amortized Cost
Without single maturity date	228,448	236,997
Total	228,448	236,997
Available for Sale Securities, Fair Value
Without single maturity date	228,448	236,997
Total	228,448	236,997
Mortgage-backed - Non-Agency multi-family
Held to Maturity Securities, Amortized Cost
Amortized Cost	710,024	719,662
Held to Maturity Securities, Fair Value
Fair Value	709,605	719,247
Mortgage-backed - Non-Agency residential
Available for Sale Securities, Amortized Cost
Without single maturity date	472,192	485,500
Total	472,192	485,500
Available for Sale Securities, Fair Value
Without single maturity date	472,192	485,500
Total	472,192	485,500
Held to Maturity Securities, Amortized Cost
Amortized Cost	453,167	472,539
Held to Maturity Securities, Fair Value
Fair Value	$ 455,465	$ 473,094

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