Schedule of recorded amount of assets and liabilities measured at fair value on a recurring basis


			Quoted Prices
			In Active		Significant
			Markets		Other		Significant
			for Identical		Observable		Unobservable
			Assets		Inputs		Inputs
(Dollars in thousands)	Fair Value		(Level 1)		(Level 2)		(Level 3)
June 30, 2023:
Assets
Derivative financial instruments	$	174,480	$	—	$	174,480	$	—
Loans held for sale		42,951		—		42,951		—
Trading securities		56,580		—		56,580		—
Securities available for sale:
U.S. Treasuries		219,913		—		219,913		—
U.S. Government agencies		218,345		—		218,345		—
Residential mortgage-backed securities issued by U.S. government
agencies or sponsored enterprises		1,604,370		—		1,604,370		—
Residential collateralized mortgage-obligations issued by U.S. government
agencies or sponsored enterprises		559,776		—		559,776		—
Commercial mortgage-backed securities issued by U.S. government
agencies or sponsored enterprises		962,494		—		962,494		—
State and municipal obligations		954,455		—		954,455		—
Small Business Administration loan-backed securities		404,559		—		404,559		—
Corporate securities		25,422		—		25,422		—
Total securities available for sale		4,949,334		—		4,949,334		—
Mortgage servicing rights		87,539		—		—		87,539
SBA servicing asset		6,202		—		—		6,202
	$	5,317,086	$	—	$	5,223,345	$	93,741
Liabilities
Derivative financial instruments	$	975,717	$	—	$	975,717	$	—

December 31, 2022:
Assets
Derivative financial instruments	$	211,016	$	—	$	211,016	$	—
Loans held for sale		28,968		—		28,968		—
Trading securities		31,263		—		31,263		—
Securities available for sale:
U.S. Treasuries		265,638		—		265,638		—
U.S. Government agencies		219,088		—		219,088		—
Residential mortgage-backed securities issued by U.S. government
agencies or sponsored enterprises		1,698,353		—		1,698,353		—
Residential collateralized mortgage-obligations issued by U.S. government
agencies or sponsored enterprises		601,045		—		601,045		—
Commercial mortgage-backed securities issued by U.S. government
agencies or sponsored enterprises		1,000,398		—		1,000,398		—
State and municipal obligations		1,064,852		—		1,064,852		—
Small Business Administration loan-backed securities		444,810		—		444,810		—
Corporate securities		32,638		—		32,638		—
Total securities available for sale		5,326,822		—		5,326,822		—
Mortgage servicing rights		86,610		—		—		86,610
SBA servicing asset		6,068		—		—		6,068
	$	5,690,747	$	—	$	5,598,069	$	92,678
Liabilities
Derivative financial instruments	$	1,034,143	$	—	$	1,034,143	$	—

Schedule of amounts of assets and liabilities measured at fair value on a nonrecurring basis


			Quoted Prices
			In Active		Significant
			Markets		Other		Significant
			for Identical		Observable		Unobservable
			Assets		Inputs		Inputs
(Dollars in thousands)	Fair Value		(Level 1)		(Level 2)		(Level 3)
June 30, 2023:
OREO	$	1,080	$	—	$	—	$	1,080
Bank properties held for sale		13,472		—		—		13,472
Individually evaluated loans		84,099		—		—		84,099
December 31, 2022:
OREO	$	1,023	$	—	$	—	$	1,023
Bank properties held for sale		17,754		—		—		17,754
Individually evaluated loans		20,802		—		—		20,802

Schedule of estimated fair value, and related carrying amount, of the Company's financial instruments


	Carrying		Fair
(Dollars in thousands)	Amount		Value		Level 1		Level 2		Level 3
June 30, 2023
Financial assets:
Cash and cash equivalents	$	1,513,749	$	1,513,749	$	1,513,749	$	—	$	—
Trading securities		56,580		56,580		—		56,580		—
Investment securities		7,731,217		7,290,576		196,728		7,093,848		—
Loans held for sale		42,951		42,951		—		42,951		—
Loans, net of allowance for credit losses		31,109,393		30,184,857		—		—		30,184,857
Accrued interest receivable		137,230		137,230		—		26,346		110,884
Mortgage servicing rights		87,539		87,539		—		—		87,539
SBA servicing asset		6,202		6,202		—		—		6,202
Interest rate swap – non-designated hedge		173,248		173,248		—		173,248		—
Other derivative financial instruments (mortgage banking related)		1,232		1,232		—		1,232		—
Financial liabilities:
Deposits
Noninterest-bearing		11,489,483		11,489,483		—		11,489,483		—
Interest-bearing other than time deposits		20,826,961		20,826,961		—		20,826,961		—
Time deposits		4,425,434		4,351,601		—		4,351,601		—
Federal funds purchased and securities sold under agreements to repurchase		581,446		581,446		—		581,446		—
Corporate and subordinated debentures		392,090		385,920		—		385,920		—
Other borrowings		400,000		400,000		—		400,000		—
Accrued interest payable		31,791		31,791		—		31,791		—
Interest rate swap – non-designated hedge		974,549		974,549		—		974,549		—
Other derivative financial instruments (mortgage banking related)		1,168		1,168		—		1,168		—
Off balance sheet financial instruments:
Commitments to extend credit		—		(328,875)		—		(328,875)		—
December 31, 2022
Financial assets:
Cash and cash equivalents	$	1,312,563	$	1,312,563	$	1,312,563	$	—	$	—
Trading securities		31,263		31,263		—		31,263		—
Investment securities		8,189,780		7,756,707		179,717		7,576,990		—
Loans held for sale		28,968		28,968		—		28,968		—
Loans, net of allowance for credit losses		29,821,418		29,329,499		—		—		29,329,499
Accrued interest receivable		134,594		134,594		—		28,449		106,145
Mortgage servicing rights		86,610		86,610		—		—		86,610
SBA servicing asset		6,068		—		—		—		6,068
Interest rate swap – non-designated hedge		210,216		210,216		—		210,216		—
Other derivative financial instruments (mortgage banking related)		800		800		—		800		—
Financial liabilities:
Deposits
Noninterest-bearing		13,168,656		13,168,656		—		13,168,656		—
Interest-bearing other than time deposits		20,761,981		20,761,981		—		20,761,981		—
Time deposits		2,419,986		2,333,764		—		2,333,764		—
Federal funds purchased and securities sold under agreements to repurchase		556,417		556,417		—		556,417		—
Corporate and subordinated debentures		392,275		377,360		—		377,360		—
Accrued interest payable		6,218		6,218		—		3,345		—
Interest rate swap – non-designated hedge		1,033,980		1,033,980		—		1,033,980		—
Other derivative financial instruments (mortgage banking related)		163		163		—		163		—
Off balance sheet financial instruments:
Commitments to extend credit		—		(184,801)		—		(184,801)		—

Schedule of reconciliation of the beginning and ending balances of Level 3 assets, comprised of Mortgage Servicing Rights, SBA servicing asset and liabilities recorded at fair value on a recurring basis


(Dollars in thousands)	MSRs
Fair value, January 1, 2023	$	86,610
Servicing assets that resulted from transfers of financial assets		4,034
Changes in fair value due to valuation inputs or assumptions		688
Changes in fair value due to decay		(3,793)
Fair value, June 30, 2023	$	87,539

Schedule of reconciliation of the beginning and ending balances of Level 3 assets, comprised of Mortgage Servicing Rights, SBA servicing asset and liabilities recorded at fair value on a recurring basis


(Dollars in thousands)	SBA Servicing Asset
Fair value, January 1, 2023	$	6,068
Servicing assets that resulted from transfers of financial assets		631
Changes in fair value due to decay		(931)
Changes in fair value due to valuation inputs or assumptions		434
Fair value, June 30, 2023	$	6,202