Investment Securities

Securities Available-for-Sale

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



	June 30, 2016									December 31, 2015
			Gross		Gross							Gross		Gross
	Amortized		Unrealized		Unrealized			Fair		Amortized		Unrealized		Unrealized			Fair
Security Type:	Cost		Gains		Losses			Value		Cost		Gains		Losses			Value
	(In thousands)
Residential mortgage-backed securities:
Government agency and
government-sponsored enterprise
pass-through securities	$	509,895	$	11,108	$	(484	)	$	520,519	$	660,069	$	11,517	$	(3,746	)	$	667,840
Government agency and
government-sponsored enterprise
collateralized mortgage obligations	161,207		4,158		(154		)	165,211		193,148		2,633		(1,026		)	194,755
Private label collateralized
mortgage obligations	144,935		5,385		(751		)	149,569		140,065		5,837		(1,106		)	144,796
Municipal securities	1,449,194		104,093		(1		)	1,553,286		1,508,968		39,435		(1,072		)	1,547,331
Government agency and
government-sponsored enterprise
commercial mortgage-backed
securities	449,096		15,584		(281		)	464,399		392,729		1,509		(2,797		)	391,441
Corporate debt securities	47,218		935		(1,426		)	46,727		49,047		327		(950		)	48,424
Collateralized loan obligations	155,309		376		(1,798		)	153,887		133,192		128		(1,131		)	132,189
SBA securities	195,621		1,977		(297		)	197,301		211,946		41		(830		)	211,157
US Treasury securities	—		—		—			—		70,196		—		(816		)	69,380
Government-sponsored enterprise debt
securities	—		—		—			—		36,302		611		—			36,913
Asset-backed and other securities	96,910		439		(702		)	96,647		116,723		119		(1,631		)	115,211
Total	$	3,209,385	$	144,055	$	(5,894	)	$	3,347,546	$	3,512,385	$	62,157	$	(15,105	)	$	3,559,437

As of June 30, 2016, securities available‑for‑sale with a carrying value of $442.9 million were pledged as collateral for borrowings, public deposits and other purposes as required by various statutes and agreements.

During the three months ended June 30, 2016, we sold $9.9 million of primarily municipal securities for a gross realized gain of $0.6 million and a gross realized loss of $0.1 million. During the three months ended June 30, 2015, we sold $14.8 million of municipal securities for a gross realized gain of $0.1 million and a gross realized loss of $0.3 million.

During the six months ended June 30, 2016, we sold $344.8 million of various securities, primarily government agency and government-sponsored enterprise ("GSE") pass-through securities and collateralized mortgage obligations, U.S. Treasury securities and GSE debt securities, for a gross realized gain of $9.5 million and a gross realized loss of $0.9 million. During the six months ended June 30, 2015, we sold $156.5 million of government agency and GSE pass-through securities, corporate debt securities, and municipal securities for a gross realized gain of $3.8 million and a gross realized loss of $0.7 million.

Unrealized Losses on Securities Available-for-Sale

The following tables present the gross unrealized losses and fair values of securities available-for-sale that were in unrealized loss positions, for which other-than-temporary impairments have not been recognized in earnings, as of the dates indicated:



	June 30, 2016
	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)
Residential mortgage-backed securities:
Government agency and government-
sponsored enterprise pass-through
securities	$	142,069	$	(465	)	$	4,618	$	(19	)	$	146,687	$	(484	)
Government agency and government-
sponsored enterprise collateralized
mortgage obligations	31,379		(154		)	—		—			31,379		(154		)
Private label collateralized mortgage
obligations	49,862		(534		)	3,058		(217		)	52,920		(751		)
Municipal securities	7,465		(1		)	—		—			7,465		(1		)
Government agency and government-
sponsored enterprise commercial
mortgage-backed securities	43,039		(281		)	—		—			43,039		(281		)
Corporate debt securities	28,792		(1,426		)	—		—			28,792		(1,426		)
Collateralized loan obligations	58,145		(685		)	53,825		(1,113		)	111,970		(1,798		)
SBA securities	53,519		(297		)	—		—			53,519		(297		)
Asset-backed and other securities	41,628		(170		)	20,993		(532		)	62,621		(702		)
Total	$	455,898	$	(4,013	)	$	82,494	$	(1,881	)	$	538,392	$	(5,894	)



	December 31, 2015
	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)
Residential mortgage-backed securities:
Government agency and government-
sponsored enterprise pass-through
securities	$	352,042	$	(3,480	)	$	9,342	$	(266	)	$	361,384	$	(3,746	)
Government agency and government-
sponsored enterprise collateralized
mortgage obligations	117,786		(1,026		)	—		—			117,786		(1,026		)
Private label collateralized mortgage
obligations	93,533		(1,000		)	1,638		(106		)	95,171		(1,106		)
Municipal securities	126,892		(1,061		)	531		(11		)	127,423		(1,072		)
Government agency and government-
sponsored enterprise commercial
mortgage-backed securities	236,098		(2,156		)	14,230		(641		)	250,328		(2,797		)
US Treasury securities	69,380		(816		)	—		—			69,380		(816		)
Corporate debt securities	29,379		(950		)	—		—			29,379		(950		)
Collateralized loan obligations	100,993		(1,131		)	—		—			100,993		(1,131		)
SBA securities	179,942		(830		)	—		—			179,942		(830		)
Asset-backed and other securities	71,619		(1,182		)	16,091		(449		)	87,710		(1,631		)
Total	$	1,377,664	$	(13,632	)	$	41,832	$	(1,473	)	$	1,419,496	$	(15,105	)

We reviewed the securities that were in a loss position at June 30, 2016, and concluded their unrealized losses were not a result of downgraded credit ratings or other indicators of deterioration of the underlying issuers' ability to repay. Such unrealized losses were a result of the level of market interest rates and pricing changes caused by shifting supply and demand dynamics relative to the types of securities. Accordingly, we determined the securities were temporarily impaired and we did not recognize such impairment in the condensed consolidated statements of earnings. Although we occasionally sell securities for portfolio management purposes, we do not foresee having to sell any temporarily impaired securities strictly for liquidity needs and believe that it is more likely than not we would not be required to sell any temporarily impaired securities before recovery of their amortized cost.

Contractual Maturities of Securities Available-for-Sale

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



	June 30, 2016
	Amortized		Fair
Maturity:	Cost		Value
	(In thousands)
Due in one year or less	$	14,761	$	14,834
Due after one year through five years	230,982		235,996
Due after five years through ten years	713,952		736,838
Due after ten years	2,249,690		2,359,878
Total securities available-for-sale	$	3,209,385	$	3,347,546

Mortgage-backed securities have contractual terms to maturity, but require periodic payments to reduce principal. In addition, expected maturities may differ from contractual maturities because obligors and/or issuers may have the right to call or prepay obligations with or without call or prepayment penalties.

Interest Income on Investment Securities

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



	Three Months Ended						Six Months Ended
	June 30,		March 31,		June 30,		June 30,
	2016		2016		2015		2016		2015
	(In thousands)
Taxable interest	$	11,406	$	11,396	$	7,577	$	22,802	$	15,050
Non-taxable interest	10,503		10,726		4,808		21,229		8,702
Dividend income	511		425		2,185		936		3,013
Total interest income on investment securities	$	22,420	$	22,547	$	14,570	$	44,967	$	26,765