Securities - Scheduled Contractual Maturities of HTM Debt Securities (Details) $ in Thousands	Dec. 31, 2025 USD ($)
Amortized cost
Within One Year	$ 0
After One Year through Five Years	694,865
After Five Years through Ten Years	748,170
After Ten Years	1,427,023
Total	2,870,058
Fair value
Within One Year	0
After One Year through Five Years	667,508
After Five Years through Ten Years	645,500
After Ten Years	1,166,738
Total	$ 2,479,746
Weighted Average Yield
Within One Year	0.00%
After One Year through Five Years	1.13%
After Five Years through Ten Years	1.89%
After Ten Years	1.79%
Total	1.66%
U.S. Treasury securities
Amortized cost
Within One Year	$ 0
After One Year through Five Years	540,666
After Five Years through Ten Years	0
After Ten Years	0
Total	540,666
Fair value
Within One Year	0
After One Year through Five Years	524,887
After Five Years through Ten Years	0
After Ten Years	0
Total	$ 524,887
Weighted Average Yield
Within One Year	0.00%
After One Year through Five Years	1.05%
After Five Years through Ten Years	0.00%
After Ten Years	0.00%
Total	1.05%
U.S. government agency and U.S. government-sponsored enterprise debt securities
Amortized cost
Within One Year	$ 0
After One Year through Five Years	105,467
After Five Years through Ten Years	556,098
After Ten Years	345,490
Total	1,007,055
Fair value
Within One Year	0
After One Year through Five Years	97,497
After Five Years through Ten Years	479,123
After Ten Years	283,514
Total	$ 860,134
Weighted Average Yield
Within One Year	0.00%
After One Year through Five Years	1.37%
After Five Years through Ten Years	1.91%
After Ten Years	2.04%
Total	1.90%
U.S. government agency and U.S. government-sponsored enterprise mortgage-backed securities
Amortized cost
Within One Year	$ 0
After One Year through Five Years	48,732
After Five Years through Ten Years	178,114
After Ten Years	910,028
Total	1,136,874
Fair value
Within One Year	0
After One Year through Five Years	45,124
After Five Years through Ten Years	153,739
After Ten Years	744,364
Total	$ 943,227
Weighted Average Yield
Within One Year	0.00%
After One Year through Five Years	1.48%
After Five Years through Ten Years	1.81%
After Ten Years	1.67%
Total	1.68%
Municipal securities
Amortized cost
Within One Year	$ 0
After One Year through Five Years	0
After Five Years through Ten Years	13,958
After Ten Years	171,505
Total	185,463
Fair value
Within One Year	0
After One Year through Five Years	0
After Five Years through Ten Years	12,638
After Ten Years	138,860
Total	$ 151,498
Weighted Average Yield
Within One Year	0.00%
After One Year through Five Years	0.00%
After Five Years through Ten Years	2.35%
After Ten Years	1.99%
Total	2.02%