Fair Value (Tables)

12 Months Ended

Dec. 31, 2021

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 December 31, 2021 and 2020, 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 years ended December 31, 2021 and 2020.

	December 31, 2021
	Total		Level 1		Level 2		Level 3
U.S. Treasury securities	$	344,640	$	344,640	$	—	$	—
U.S. Government agency obligations		13,727		—		13,727		—
Obligations of states and political subdivisions		5,714		—		5,714		—
Mortgage-backed securities		2,874,796		—		2,874,796		—
Securities available for sale		3,238,877		344,640		2,894,237		—
LHFS		275,706		—		275,706		—
MSR		87,687		—		—		87,687
Other assets - derivatives		24,809		2,794		20,156		1,859
Other liabilities - derivatives		4,677		414		4,263		—

	December 31, 2020
	Total		Level 1		Level 2		Level 3
U.S. Government agency obligations	$	18,041	$	—	$	18,041	$	—
Obligations of states and political subdivisions		5,835		—		5,835		—
Mortgage-backed securities		1,967,939		—		1,967,939		—
Securities available for sale		1,991,815		—		1,991,815		—
LHFS		446,951		—		446,951		—
MSR		66,464		—		—		66,464
Other assets - derivatives		47,768		145		38,063		9,560
Other liabilities - derivatives		5,324		666		4,658		—

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 years ended December 31, 2021 and 2020 are summarized as follows ($ in thousands):

	MSR			Other Assets - Derivatives
Balance, January 1, 2021	$	66,464		$	9,560
Total net (loss) gain included in Mortgage banking, net (1)		(6,902	)		9,104
Additions		28,125			—
Sales		—			(16,805	)
Balance, December 31, 2021	$	87,687		$	1,859
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    December 31, 2021	$	13,258		$	3,159
Balance, January 1, 2020	$	79,394		$	1,439
Total net (loss) gain included in Mortgage banking, net (1)		(42,735	)		40,669
Additions		29,805			—
Sales		—			(32,548	)
Balance, December 31, 2020	$	66,464		$	9,560
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    December 31, 2020	$	(26,146	)	$	25,031

(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 December 31, 2021 and 2020 were as follows ($ in thousands):

	December 31, 2021				December 31, 2020
	Carrying  Value		Estimated Fair Value		Carrying Value		Estimated Fair Value
Financial Assets:
Level 2 Inputs:
Cash and short-term investments	$	2,266,829	$	2,266,829	$	1,952,554	$	1,952,554
Securities held to maturity		342,537		353,511		538,072		563,115
Level 3 Inputs:
Net LHFI and PPP loans		10,181,708		10,123,379		10,317,352		10,312,395
Financial Liabilities:
Level 2 Inputs:
Deposits		15,087,160		15,084,440		14,048,764		14,052,863
Federal funds purchased and securities sold under    repurchase agreements		238,577		238,577		164,519		164,519
Other borrowings		91,025		91,022		168,252		168,252
Subordinated notes		123,042		128,438		122,921		127,500
Junior subordinated debt securities		61,856		49,485		61,856		46,083

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 the LHFS accounted for under the fair value option at December 31, 2021 and 2020 ($ in thousands):

	December 31,
	2021		2020
Fair value of LHFS	$	191,242	$	305,791
LHFS contractual principal outstanding		186,535		290,625
Fair value less unpaid principal	$	4,707	$	15,166