Securities - Narrative (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025	Dec. 31, 2025
Debt Securities, Available-for-sale [Line Items]
Proceeds from sale of available-for-sale debt securities, including legacy securities	$ 234,000,000.0		$ 511,100,000
Gross losses from sale of securities	100,000		39,600,000
Unrealized losses on mortgage backed securities of government sponsored entities	349,762,000		349,762,000		$ 150,385,000
Fair value of securities in unrealized loss position	4,445,392,000		4,445,392,000		2,040,898,000
Held-to-maturity securities, allowance for credit loss	0		0
Federal home loan bank and federal reserve stock recorded in other assets	143,900,000		143,900,000		135,600,000
Accrued interest receivable on AFS debt securities	22,500,000		22,500,000		24,500,000
Accrued interest receivable on HTM debt securities	900,000		900,000		1,000,000.0
Asset Pledged as Collateral
Debt Securities, Available-for-sale [Line Items]
Fair value of debt securities pledged as collateral	2,200,000,000		2,200,000,000
Other debt securities
Debt Securities, Available-for-sale [Line Items]
Proceeds from sale of available-for-sale debt securities, including legacy securities		$ 19,800,000		$ 19,800,000
Gross losses from sale of securities		1,000,000.0		1,000,000.0
Unrealized losses on mortgage backed securities of government sponsored entities	6,960,000		6,960,000		576,000
Fair value of securities in unrealized loss position	153,813,000		153,813,000		132,345,000
CRA - Qualified Mutual Fund
Debt Securities, Available-for-sale [Line Items]
Gross losses from sale of securities	500,000		700,000
Gross gains from sale of securities		100,000		$ 400,000
Investment in mutual fund carried at fair value	13,300,000		13,300,000		13,900,000
U.S. Treasury securities and obligations of U.S. government agencies
Debt Securities, Available-for-sale [Line Items]
Unrealized losses on mortgage backed securities of government sponsored entities	2,702,000		2,702,000		451,000
Fair value of securities in unrealized loss position	55,192,000		55,192,000		35,778,000
Allowance for credit losses on AFS debt securities	0		0
Mortgage-backed securities and collateralized mortgage obligations of U.S. government-sponsored entities
Debt Securities, Available-for-sale [Line Items]
Unrealized losses on mortgage backed securities of government sponsored entities	309,000,000.0		309,000,000.0
Fair value of securities in unrealized loss position	3,600,000,000		3,600,000,000
Allowance for credit losses on AFS debt securities	0		0
Private mortgage-backed securities and collateralized mortgage obligations
Debt Securities, Available-for-sale [Line Items]
Unrealized losses on mortgage backed securities of government sponsored entities	6,590,000		6,590,000		5,010,000
Fair value of securities in unrealized loss position	71,533,000		71,533,000		77,798,000
Allowance for credit losses on AFS debt securities	$ 0		$ 0
Average credit support percentage	22.00%		22.00%
CLOs
Debt Securities, Available-for-sale [Line Items]
Unrealized losses on mortgage backed securities of government sponsored entities	$ 858,000		$ 858,000		512,000
Fair value of securities in unrealized loss position	241,439,000		241,439,000		249,934,000
Allowance for credit losses on AFS debt securities	$ 0		$ 0
CLOs | Standard & Poor's, AAA Rating
Debt Securities, Available-for-sale [Line Items]
Number of positions held, percentage of total	37.00%		37.00%
CLOs | Standard & Poor's, AA Rating
Debt Securities, Available-for-sale [Line Items]
Number of positions held, percentage of total	23.00%		23.00%
Obligations of state and political subdivisions
Debt Securities, Available-for-sale [Line Items]
Unrealized losses on mortgage backed securities of government sponsored entities	$ 23,647,000		$ 23,647,000		2,520,000
Fair value of securities in unrealized loss position	310,132,000		310,132,000		$ 249,898,000
Allowance for credit losses on AFS debt securities	$ 0		$ 0
Heartland Bancshares, Inc
Debt Securities, Available-for-sale [Line Items]
Proceeds from sale of available-for-sale debt securities, including legacy securities		$ 245,700,000