Investment Securities - Analysis of the Contractual Maturities of Investment Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Available-for-sale Securities, Debt Maturities, Single Maturity Date, Amortized Cost Basis Rolling Maturity[Abstract]
Due in One Year or Less	$ 8,299
Due After One Year Through Five Years	420,864
Due After Five Years Through Ten Years	728,474
Due After Ten Years	6,380
Amortized Cost, Total	1,164,017
Available-for-sale Securities, Debt Maturities, Single Maturity Date, Rolling Maturities [Abstract]
Available-for-Sale: Amortized Cost	3,172,436	$ 4,320,884
Due in One Year or Less	8,284
Due After One Year Through Five Years	400,125
Due After Five Years Through Ten Years	667,094
Due After Ten Years	4,989
Fair Value, Total	1,080,492
Available-for-Sale: Fair Value	2,844,823	4,276,056
Held-to-maturity Securities, Debt Maturities, Single Maturity Date, Amortized Cost Basis, Rolling Maturities (Abstract]
Due After One Year Through Five Years	13,494
Due After Five Years Through Ten Years	124,119
Due After Ten Years	11,020
Amortized Cost, Total	148,633
Held-to-Maturity Securities, Debt Maturities, Single Maturity Date, Fair Value, Rolling Maturities [Abstract]
Held-to-Maturity: Amortized Cost	5,414,139
Due After One Year Through Five Years	12,520
Due After Five Years Through Ten Years	106,682
Due After Ten Years	8,695
Fair Value, Total	127,897
Held-to-Maturity: Fair Value	4,615,393	4,646,619
Debt Securities Issued by Government Agencies
Available-for-sale Securities, Debt Maturities, Single Maturity Date, Rolling Maturities [Abstract]
Available-for-sale Securities: Amortized Cost	91,399
Available-for-sale Securities, Debt Securities Issued by Government Agencies and Mortgage-Backed Securities: Fair Value	91,965
Residential - Government Agencies
Available-for-sale Securities, Debt Maturities, Single Maturity Date, Rolling Maturities [Abstract]
Available-for-sale Securities: Amortized Cost	828,798
Available-for-Sale: Amortized Cost	828,798	1,327,990
Available-for-sale Securities, Debt Securities Issued by Government Agencies and Mortgage-Backed Securities: Fair Value	732,828
Available-for-Sale: Fair Value	732,828	1,319,042
Held-to-Maturity Securities, Debt Maturities, Single Maturity Date, Fair Value, Rolling Maturities [Abstract]
Held-to-Maturity: Mortgage-Backed Securities: Amortized Cost	1,848,239
Held-to-Maturity: Mortgage-Backed Securities: Fair Value	1,554,227
Held-to-Maturity: Fair Value	1,554,227	1,755,912
Residential - U.S. Government-Sponsored Enterprises
Available-for-sale Securities, Debt Maturities, Single Maturity Date, Rolling Maturities [Abstract]
Available-for-sale Securities: Amortized Cost	919,980
Available-for-Sale: Amortized Cost	919,980	2,127,781
Available-for-sale Securities, Debt Securities Issued by Government Agencies and Mortgage-Backed Securities: Fair Value	793,871
Available-for-Sale: Fair Value	793,871	2,090,326
Held-to-Maturity Securities, Debt Maturities, Single Maturity Date, Fair Value, Rolling Maturities [Abstract]
Held-to-Maturity: Mortgage-Backed Securities: Amortized Cost	2,968,322
Held-to-Maturity: Mortgage-Backed Securities: Fair Value	2,571,275
Held-to-Maturity: Fair Value	2,571,275	2,269,761
Commercial - Government Agencies - Sponsored Agencies
Available-for-sale Securities, Debt Maturities, Single Maturity Date, Rolling Maturities [Abstract]
Available-for-sale Securities: Amortized Cost	168,242
Available-for-Sale: Amortized Cost	168,242	155,164
Available-for-sale Securities, Debt Securities Issued by Government Agencies and Mortgage-Backed Securities: Fair Value	145,667
Available-for-Sale: Fair Value	145,667	155,890
Held-to-Maturity Securities, Debt Maturities, Single Maturity Date, Fair Value, Rolling Maturities [Abstract]
Held-to-Maturity: Mortgage-Backed Securities: Amortized Cost	448,945
Held-to-Maturity: Mortgage-Backed Securities: Fair Value	361,994
Held-to-Maturity: Fair Value	361,994	469,664
Mortgage-Backed Securities
Available-for-sale Securities, Debt Maturities, Single Maturity Date, Rolling Maturities [Abstract]
Available-for-sale Securities: Amortized Cost	1,917,020
Available-for-Sale: Amortized Cost	1,917,020	3,610,935
Available-for-sale Securities, Debt Securities Issued by Government Agencies and Mortgage-Backed Securities: Fair Value	1,672,366
Available-for-Sale: Fair Value	1,672,366	3,565,258
Held-to-Maturity Securities, Debt Maturities, Single Maturity Date, Fair Value, Rolling Maturities [Abstract]
Held-to-Maturity: Mortgage-Backed Securities: Amortized Cost	5,265,506
Held-to-Maturity: Mortgage-Backed Securities: Fair Value	4,487,496
Held-to-Maturity: Fair Value	$ 4,487,496	$ 4,495,337