Schedule of amortized cost and fair value of investment securities available for sale


			Gross		Gross
	Amortized		Unrealized		Unrealized		Fair
(Dollars in thousands)	Cost		Gains		Losses		Value
December 31, 2020:
Government-sponsored entities debt*	$	29,882	$	16	$	(642)	$	29,256
State and municipal obligations		502,575		17,491		(27)		520,039
Mortgage-backed securities**		2,722,018		49,153		(3,496)		2,767,675
Corporate securities		13,562		140		—		13,702
	$	3,268,037	$	66,800	$	(4,165)	$	3,330,672
December 31, 2019:
Government-sponsored entities debt*	$	25,356	$	585	$	—	$	25,941
State and municipal obligations		204,150		5,029		(764)		208,415
Mortgage-backed securities**		1,711,257		14,209		(3,775)		1,721,691
	$	1,940,763	$	19,823	$	(4,539)	$	1,956,047

* The Company’s government-sponsored entities holdings are comprised of debt securities offered by Federal Home Loan Mortgage Corporation (“FHLMC”) or Freddie Mac, Federal National Mortgage Association (“FNMA”) or Fannie Mae, FHLB, and Federal Farm Credit Banks (“FFCB”).

** All of the mortgage-backed securities are issued by government-sponsored entities; there are no private-label holdings. Also included in the Company’s government-sponsored entities are debt securities offered by the Small Business Administration (“SBA”), which have the full faith and credit backing of the United States Government.

Schedule of amortized cost and fair value of debt and equity securities by contractual maturity


	Securities				Securities
	Held-to-maturity				Available-for-sale
	Amortized		Fair		Amortized		Fair
(Dollars in thousands)	Cost		Value		Cost		Value
Due in one year or less	$	—	$	—	$	9,669	$	9,698
Due after one year through five years		—		—		80,846		83,586
Due after five years through ten years		88,735		89,007		525,547		539,905
Due after ten years		866,807		868,176		2,651,975		2,697,483
	$	955,542	$	957,183	$	3,268,037	$	3,330,672

Schedule of securities with gross unrealized losses, aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position


	Less Than				Twelve Months
	Twelve Months				or More
	Gross				Gross
	Unrealized		Fair		Unrealized		Fair
(Dollars in thousands)	Losses		Value		Losses		Value
December 31, 2020:
Securities Held-to-maturity
Mortgage-backed securities	$	1,123	$	240,591	$	—	$	—
	$	1,123	$	240,591	$	—	$	—
Securities Available-for-sale
Government-sponsored entities debt	$	642	$	24,358	$	—	$	—
State and municipal obligations		27		8,620		—		—
Mortgage-backed securities		2,475		509,319		1,021		105,125
	$	3,144	$	542,297	$	1,021	$	105,125
December 31, 2019:
Securities Available-for-sale
Government-sponsored entities debt	$	—	$	—	$	—	$	—
State and municipal obligations		764		42,070		—		—
Mortgage-backed securities		2,422		461,658		1,353		141,982
	$	3,186	$	503,728	$	1,353	$	141,982