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, 2021:
Assets
Derivative financial instruments	$	526,145	$	—	$	526,145	$	—
Loans held for sale		171,447		—		171,447		—
Trading securities		89,925		—		89,925		—
Securities available for sale:
U.S. Government agencies		48,137		—		48,137		—
Residential mortgage-backed securities issued by U.S. government
agencies or sponsored enterprises		1,666,127		—		1,666,127		—
Residential collateralized mortgage-obligations issued by U.S. government
agencies or sponsored enterprises		666,777		—		666,777		—
Commercial mortgage-backed securities issued by U.S. government
agencies or sponsored enterprises		812,613		—		812,613		—
State and municipal obligations		693,128		—		693,128		—
Small Business Administration loan-backed securities		468,485		—		468,485		—
Corporate securities		13,892		—		13,892		—
Total securities available for sale		4,369,159		—		4,369,159		—
Mortgage servicing rights		57,351		—		—		57,351
	$	5,214,027	$	—	$	5,156,676	$	57,351
Liabilities
Derivative financial instruments	$	518,221	$	—	$	518,221	$	—

December 31, 2020:
Assets
Derivative financial instruments	$	813,899	$	—	$	813,899	$	—
Loans held for sale		290,467		—		290,467		—
Trading securities		10,674		—		10,674		—
Securities available for sale:
U.S. Government agencies		29,256		—		29,256		—
Residential mortgage-backed securities issued by U.S. government
agencies or sponsored enterprises		1,367,132		—		1,367,132		—
Residential collateralized mortgage-obligations issued by U.S. government
agencies or sponsored enterprises		755,551		—		755,551		—
Commercial mortgage-backed securities issued by U.S. government
agencies or sponsored enterprises		240,108		—		240,108		—
State and municipal obligations		520,039		—		520,039		—
Small Business Administration loan-backed securities		404,884		—		404,884		—
Corporate securities		13,702		—		13,702		—
Total securities available for sale		3,330,672		—		3,330,672		—
Mortgage servicing rights		43,820		—		—		43,820
	$	4,489,532	$	—	$	4,445,712	$	43,820
Liabilities
Derivative financial instruments	$	804,832	$	—	$	804,832	$	—

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, 2021:
OREO	$	5,039	$	—	$	—	$	5,039
Bank property held for sale		20,237		—		—		20,237
Impaired loans		8,891		—		—		8,891
December 31, 2020:
OREO	$	11,914	$	—	$	—	$	11,914
Bank property held for sale		36,006		—		—		36,006
Impaired loans		17,609		—		—		17,609

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, 2021
Financial assets:
Cash and cash equivalents	$	6,404,512	$	6,404,512	$	6,404,512	$	—	$	—
Trading securities		89,925		89,925		—		89,925		—
Investment securities		5,719,031		5,698,158		160,607		5,537,551		—
Loans held for sale		171,447		171,447		—		171,447		—
Loans, net of allowance for loan losses		23,682,677		23,845,019		—		—		23,845,019
Accrued interest receivable		99,138		99,138		—		16,015		83,123
Mortgage servicing rights		57,351		57,351		—		—		57,351
Interest rate swap - non-designated hedge		516,632		516,632		—		516,632		—
Other derivative financial instruments (mortgage banking related)		9,513		9,513		—		9,513		—
Financial liabilities:
Deposits		33,242,369		33,254,282		—		33,254,282		—
Federal funds purchased and securities sold under agreements to repurchase		862,429		862,429		—		862,429		—
Other borrowings		351,548		350,466		—		350,466		—
Accrued interest payable		4,774		4,774		—		4,774		—
Interest rate swap - non-designated hedge		518,221		518,221		—		518,221		—
Off balance sheet financial instruments:
Commitments to extend credit		—		45,968		—		45,968		—
December 31, 2020
Financial assets:
Cash and cash equivalents	$	4,609,255	$	4,609,255	$	4,609,255	$	—	$	—
Trading securities		10,674		10,674		—		10,674		—
Investment securities		4,446,657		4,448,300		160,443		4,287,857		—
Loans held for sale		290,467		290,467		—		290,467		—
Loans, net of allowance for loan losses		24,206,825		24,757,859		—		—		24,757,859
Accrued interest receivable		107,601		107,601		—		12,952		94,649
Mortgage servicing rights		43,820		43,820		—		—		43,820
Interest rate swap - non-designated hedge		802,763		802,763		—		802,763		—
Other derivative financial instruments (mortgage banking related)		11,136		11,136		—		11,136		—
Financial liabilities:
Deposits		30,693,882		30,719,416		—		30,719,416		—
Federal funds purchased and securities sold under agreements to repurchase		779,666		779,666		—		779,666		—
Other borrowings		390,179		386,126		—		386,126		—
Accrued interest payable		7,103		7,103		—		7,103		—
Interest rate swap - non-designated hedge		804,832		804,832		—		804,832		—
Off balance sheet financial instruments:
Commitments to extend credit		—		136,726		—		136,726		—