Investment Securities (Tables)

3 Months Ended

Mar. 31, 2021

Investments, Debt and Equity Securities [Abstract]

Schedule of available-for-sale securities reconciliation

The following table presents amortized cost, gross unrealized gains and losses, and fair values of securities available-for-sale as of the dates indicated:

	March 31, 2021								December 31, 2020
			Gross		Gross						Gross		Gross
	Amortized		Unrealized		Unrealized		Fair		Amortized		Unrealized		Unrealized		Fair
Security Type	Cost		Gains		Losses		Value		Cost		Gains		Losses		Value
	(In thousands)
Municipal securities	$	1,589,855	$	65,063	$	(8,864)	$	1,646,054	$	1,438,004	$	93,631	$	(18)	$	1,531,617
Agency commercial MBS	1,227,960		51,944		(6,502)		1,273,402		1,207,676		74,238		(37)		1,281,877
Agency residential CMOs	1,073,402		38,771		(3,345)		1,108,828		1,172,166		47,994		(280)		1,219,880
U.S. Treasury securities	500,902		276		(9,820)		491,358		4,989		313		—		5,302
Agency residential MBS	422,955		12,337		(2,192)		433,100		329,488		12,483		(897)		341,074
Corporate debt securities	377,280		5,674		(2,547)		380,407		308,803		3,490		(404)		311,889
Collateralized loan obligations	244,946		204		(910)		244,240		136,777		23		(924)		135,876
Asset-backed securities	222,709		1,848		(542)		224,015		248,739		1,534		(770)		249,503
Private label residential CMOs	98,958		4,728		(310)		103,376		110,891		6,076		(21)		116,946
SBA securities	35,726		1,218		(34)		36,910		39,437		2,217		(27)		41,627
Total	$	5,794,693	$	182,063	$	(35,066)	$	5,941,690	$	4,996,970	$	241,999	$	(3,378)	$	5,235,591

Schedule of realized gains and losses on securities available-for-sale

The following table presents the amortized cost of securities sold with related gross realized gains, gross realized losses, and net realized gains for the years indicated:

	Three Months Ended
	March 31,
Sales of Securities Available-for-Sale	2021		2020
	(In thousands)
Amortized cost of securities sold	$	44,551	$	14,766
Gross realized gains	$	101	$	182
Net realized gains	$	101	$	182

Unrealized losses on investment securities

The following tables present the gross unrealized losses and fair values of securities available-for-sale that were in unrealized loss positions as of the dates indicated:

	March 31, 2021
	Less Than 12 Months				12 Months or More				Total
			Gross				Gross				Gross
	Fair		Unrealized		Fair		Unrealized		Fair		Unrealized
Security Type	Value		Losses		Value		Losses		Value		Losses
	(In thousands)
Municipal securities	$	446,081	$	(8,864)	$	—	$	—	$	446,081	$	(8,864)
Agency commercial MBS	177,833		(6,502)		—		—		177,833		(6,502)
Agency residential CMOs	148,694		(3,345)		—		—		148,694		(3,345)
U.S. Treasury securities	486,092		(9,820)		—		—		486,092		(9,820)
Agency residential MBS	186,057		(2,172)		1,330		(20)		187,387		(2,192)
Corporate debt securities	150,214		(2,547)		—		—		150,214		(2,547)
Collateralized loan obligations	82,027		(593)		48,694		(317)		130,721		(910)
Asset-backed securities	27,843		(72)		44,246		(470)		72,089		(542)
Private label residential CMOs	29,344		(308)		365		(2)		29,709		(310)
SBA securities	—		—		1,917		(34)		1,917		(34)
Total	$	1,734,185	$	(34,223)	$	96,552	$	(843)	$	1,830,737	$	(35,066)

	December 31, 2020
	Less Than 12 Months				12 Months or More				Total
			Gross				Gross				Gross
	Fair		Unrealized		Fair		Unrealized		Fair		Unrealized
Security Type	Value		Losses		Value		Losses		Value		Losses
	(In thousands)
Municipal securities	$	5,919	$	(18)	$	—	$	—	$	5,919	$	(18)
Agency commercial MBS	58,408		(37)		—		—		58,408		(37)
Agency residential CMOs	97,863		(280)		—		—		97,863		(280)
Agency residential MBS	90,722		(897)		—		—		90,722		(897)
Corporate debt securities	87,596		(404)		—		—		87,596		(404)
Collateralized loan obligations	96,442		(729)		28,972		(195)		125,414		(924)
Asset-backed securities	17,694		(63)		61,031		(707)		78,725		(770)
Private label residential CMOs	788		(19)		74		(2)		862		(21)
SBA securities	2,127		(27)		—		—		2,127		(27)
Total	$	457,559	$	(2,474)	$	90,077	$	(904)	$	547,636	$	(3,378)

Investments classified by contractual maturity date

The following table presents the contractual maturities of our securities available-for-sale portfolio based on amortized cost and carrying value as of the date indicated:

	March 31, 2021
	Amortized		Fair
Maturities	Cost		Value
	(In thousands)
Due in one year or less	$	16,309	$	16,075
Due after one year through five years	571,182		598,902
Due after five years through ten years	1,963,578		1,989,510
Due after ten years	3,243,624		3,337,203
Total securities available-for-sale	$	5,794,693	$	5,941,690

Investment income

The following table presents the composition of our interest income on investment securities for the periods indicated:

	Three Months Ended
	March 31,
	2021		2020
	(In thousands)
Taxable interest	$	21,970	$	21,786
Non-taxable interest	8,078		5,229
Dividend income	217		431
Total interest income on investment securities	$	30,265	$	27,446