Investment Securities - Analysis of the Contractual Maturities of Investment Securities (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Available-for-sale Securities, Debt Maturities, Single Maturity Date, Amortized Cost Basis Rolling Maturity[Abstract]
Due in One Year or Less	$ 22,758
Due After One Year Through Five Years	439,032
Due After Five Years Through Ten Years	475,150
Amortized Cost, Total	936,940
Available-for-sale Securities, Debt Maturities, Single Maturity Date, Rolling Maturities [Abstract]
Available-for-Sale: Amortized Cost	2,585,893	$ 2,694,012
Due in One Year or Less	22,268
Due After One Year Through Five Years	409,582
Due After Five Years Through Ten Years	441,975
Fair Value, Total	873,825
Available-for-Sale: Fair Value	2,298,092	2,408,933
Held-to-maturity Securities, Debt Maturities, Single Maturity Date, Amortized Cost Basis, Rolling Maturities (Abstract]
Due in One Year or Less	244
Due After One Year Through Five Years	82,286
Due After Five Year Through Ten Years	60,142
Amortized Cost, Total	142,672
Held-to-Maturity Securities, Debt Maturities, Single Maturity Date, Fair Value, Rolling Maturities [Abstract]
Held-to-Maturity: Amortized Cost	4,812,954
Due in One Year or Less	242
Due After One Year Through Five Years	73,729
Due After Five Year Through Ten Years	49,950
Fair Value, Total	123,921
Held-to-Maturity: Fair Value	4,002,122	4,253,637
Debt Securities Issued by Government Agencies
Available-for-sale Securities, Debt Maturities, Single Maturity Date, Rolling Maturities [Abstract]
Available-for-sale Securities: Amortized Cost	54,881
Available-for-sale Securities, Debt Securities Issued by Government Agencies and Mortgage-Backed Securities: Fair Value	55,131
Residential - Government Agencies
Available-for-sale Securities, Debt Maturities, Single Maturity Date, Rolling Maturities [Abstract]
Available-for-sale Securities: Amortized Cost	666,354
Available-for-Sale: Amortized Cost	666,354	713,918
Available-for-sale Securities, Debt Securities Issued by Government Agencies and Mortgage-Backed Securities: Fair Value	578,929
Available-for-Sale: Fair Value	578,929	629,327
Held-to-Maturity Securities, Debt Maturities, Single Maturity Date, Fair Value, Rolling Maturities [Abstract]
Held-to-Maturity: Mortgage-Backed Securities: Amortized Cost	1,595,881
Held-to-Maturity: Mortgage-Backed Securities: Fair Value	1,317,947
Held-to-Maturity: Fair Value	1,317,947	1,408,603
Residential - U.S. Government-Sponsored Enterprises
Available-for-sale Securities, Debt Maturities, Single Maturity Date, Rolling Maturities [Abstract]
Available-for-sale Securities: Amortized Cost	773,094
Available-for-Sale: Amortized Cost	773,094	818,296
Available-for-sale Securities, Debt Securities Issued by Government Agencies and Mortgage-Backed Securities: Fair Value	659,946
Available-for-Sale: Fair Value	659,946	709,127
Held-to-Maturity Securities, Debt Maturities, Single Maturity Date, Fair Value, Rolling Maturities [Abstract]
Held-to-Maturity: Mortgage-Backed Securities: Amortized Cost	2,643,443
Held-to-Maturity: Mortgage-Backed Securities: Fair Value	2,224,205
Held-to-Maturity: Fair Value	2,224,205	2,374,138
Commercial - Government Agencies or Sponsored Agencies
Available-for-sale Securities, Debt Maturities, Single Maturity Date, Rolling Maturities [Abstract]
Available-for-sale Securities: Amortized Cost	154,624
Available-for-Sale: Amortized Cost	154,624	157,515
Available-for-sale Securities, Debt Securities Issued by Government Agencies and Mortgage-Backed Securities: Fair Value	130,261
Available-for-Sale: Fair Value	130,261	134,923
Held-to-Maturity Securities, Debt Maturities, Single Maturity Date, Fair Value, Rolling Maturities [Abstract]
Held-to-Maturity: Mortgage-Backed Securities: Amortized Cost	430,958
Held-to-Maturity: Mortgage-Backed Securities: Fair Value	336,049
Held-to-Maturity: Fair Value	336,049	344,880
Mortgage-Backed Securities
Available-for-sale Securities, Debt Maturities, Single Maturity Date, Rolling Maturities [Abstract]
Available-for-sale Securities: Amortized Cost	1,594,072
Available-for-Sale: Amortized Cost	1,594,072	1,689,729
Available-for-sale Securities, Debt Securities Issued by Government Agencies and Mortgage-Backed Securities: Fair Value	1,369,136
Available-for-Sale: Fair Value	1,369,136	1,473,377
Held-to-Maturity Securities, Debt Maturities, Single Maturity Date, Fair Value, Rolling Maturities [Abstract]
Held-to-Maturity: Mortgage-Backed Securities: Amortized Cost	4,670,282
Held-to-Maturity: Mortgage-Backed Securities: Fair Value	3,878,201
Held-to-Maturity: Fair Value	$ 3,878,201	$ 4,127,621