Fair Value (Tables)

3 Months Ended

Mar. 31, 2024

Fair Value Disclosures [Abstract]

Financial Assets and Liabilities Measured at Fair Value Recurring Basis

The following tables summarize financial assets and financial liabilities measured at fair value on a recurring basis at March 31, 2024 and December 31, 2023, segregated by the level of valuation inputs within the fair value hierarchy utilized to measure fair value ($ in thousands). There were no transfers between fair value levels for the three months ended March 31, 2024 and the year ended December 31, 2023.

	March 31, 2024
	Total		Level 1		Level 2		Level 3
U.S. Treasury securities	$	372,424	$	372,424	$	—	$	—
U.S. Government agency obligations		5,594		—		5,594		—
Mortgage-backed securities		1,324,281		—		1,324,281		—
Securities available for sale		1,702,299		372,424		1,329,875		—
LHFS		172,937		—		172,937		—
MSR		138,044		—		—		138,044
Other assets - derivatives		16,953		1,152		14,644		1,157
Other liabilities - derivatives		40,803		102		40,701		—

	December 31, 2023
	Total		Level 1		Level 2		Level 3
U.S. Treasury securities	$	372,368	$	372,368	$	—	$	—
U.S. Government agency obligations		5,792		—		5,792		—
Mortgage-backed securities		1,384,718		—		1,384,718		—
Securities available for sale		1,762,878		372,368		1,390,510		—
LHFS		184,812		—		184,812		—
MSR		131,870		—		—		131,870
Other assets - derivatives		23,316		7,685		14,786		845
Other liabilities - derivatives		35,600		21		35,579		—

Changes in Level 3 Assets Measured at Fair Value on a Recurring Basis

The changes in Level 3 assets measured at fair value on a recurring basis for the three months ended March 31, 2024 and 2023 are summarized as follows ($ in thousands):

	MSR			Other Assets - Derivatives
Balance, January 1, 2024	$	131,870		$	845
Total net (loss) gain included in Mortgage banking, net (1)		3,197			1,047
Additions		2,977			—
Sales		—			(735	)
Balance, March 31, 2024	$	138,044		$	1,157
The amount of total gains (losses) for the period included in earnings    that are attributable to the change in unrealized gains or    losses still held at March 31, 2024	$	5,123		$	927
Balance, January 1, 2023	$	129,677		$	157
Total net (loss) gain included in Mortgage banking, net (1)		(5,117	)		1,288
Additions		2,646			—
Sales		—			(105	)
Balance, March 31, 2023	$	127,206		$	1,340
The amount of total gains (losses) for the period included in    earnings that are attributable to the change in unrealized    gains or losses still held at March 31, 2023	$	(3,972	)	$	531

(1)Total net (loss) gain included in Mortgage banking, net relating to the MSR includes changes in fair value due to market changes and due to run-off.

Carrying Amounts and Estimated Fair Values of Financial Instruments

The carrying amounts and estimated fair values of financial instruments at March 31, 2024 and December 31, 2023, are as follows ($ in thousands):

	March 31, 2024				December 31, 2023
	Carrying Value		Estimated Fair Value		Carrying Value		Estimated Fair Value
Financial Assets:
Level 2 Inputs:
Cash and short-term investments	$	606,261	$	606,261	$	975,543	$	975,543
Securities held to maturity		1,415,025		1,333,014		1,426,279		1,355,504
Level 3 Inputs:
Net LHFI		12,914,945		12,809,237		12,811,157		12,762,505
Financial Liabilities:
Level 2 Inputs:
Deposits		15,338,557		15,320,852		15,569,763		15,553,417
Federal funds purchased and securities sold under    repurchase agreements		393,215		393,215		405,745		405,745
Other borrowings		482,027		482,024		483,230		483,226
Subordinated notes		123,537		110,625		123,482		108,125
Junior subordinated debt securities		61,856		47,011		61,856		48,856

Fair Value and the Contractual Principal Outstanding of the LHFS

The following table provides information about the fair value and the contractual principal outstanding of LHFS accounted for under the fair value option at March 31, 2024 and December 31, 2023 ($ in thousands):

	March 31, 2024		December 31, 2023
Fair value of LHFS	$	95,197	$	105,974
LHFS contractual principal outstanding		93,598		102,994
Fair value less unpaid principal	$	1,599	$	2,980