Investment Securities (Tables)

3 Months Ended

Mar. 31, 2019

Investments Debt And Equity Securities [Abstract]

Summary of Amortized Cost and Estimated Fair Value of Securities Available -for- Sale

A summary of amortized cost and estimated fair value of securities available-for-sale at March 31, 2019 and December 31, 2018 is as follows:

(In thousands)	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Estimated Fair Value
March 31, 2019
Securities available-for-sale:
U.S. Treasury securities	$	100,372	$	—	$	2,806	$	97,566
Obligations of U.S. government agencies		118,498		596		227		118,867
Mortgage-backed securities issued or guaranteed by U.S. agencies (MBS)
Residential pass-through:
Guaranteed by GNMA		92,698		497		1,143		92,052
Issued by FNMA and FHLMC		764,369		3,999		4,659		763,709
Other residential mortgage-backed securities		319,706		2,275		752		321,229
Commercial mortgage-backed securities		134,345		1,101		3,134		132,312
Total MBS		1,311,118		7,872		9,688		1,309,302
Obligations of states and municipal subdivisions		229,723		1,949		2,568		229,104
Total securities available-for-sale	$	1,759,711	$	10,417	$	15,289	$	1,754,839

(In thousands)	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Estimated Fair Value
December 31, 2018
Securities available-for-sale:
U.S. Treasury securities	$	100,413	$	—	$	3,628	$	96,785
Obligations of U.S. government agencies		60,975		316		284		61,007
Mortgage-backed securities issued or guaranteed by U.S. agencies (MBS)
Residential pass-through:
Guaranteed by GNMA		85,052		146		2,093		83,105
Issued by FNMA and FHLMC		594,874		694		10,367		585,201
Other residential mortgage-backed securities		36,339		8		1,178		35,169
Commercial mortgage-backed securities		114,383		287		5,255		109,415
Total MBS		830,648		1,135		18,893		812,890
Obligations of states and municipal subdivisions		229,475		207		13,112		216,570
Total securities available-for-sale	$	1,221,511	$	1,658	$	35,917	$	1,187,252

Schedule of Contractual Maturities of Securities Available-for-Sale

The scheduled contractual maturities of securities available-for-sale at March 31, 2019 were as follows:

	Available-for-Sale
	Amortized		Estimated
(In thousands)	Cost		Fair Value
Due in one year or less		39,560		39,596
Due after one year through five years		128,883		126,188
Due after five years through ten years		50,865		51,521
Due after ten years		229,285		228,232
Mortgage-backed securities		1,311,118		1,309,302
Total	$	1,759,711	$	1,754,839

Summary of Gross Gains, and Gross Losses on Sales of Securities Available for Sale

Gross gains and gross losses on sales of securities available for sale for the three months ended March 31, 2019 and 2018 are presented below.

	For the Three Months Ended March 31,
(In thousands)	2019			2018
Gross realized gains	$	3		$	12
Gross realized losses		(15	)		—
Realized (losses) gains on sale of securities available for sale, net	$	(12	)	$	12

Schedule of Securities Classified as Available-for-Sale with Gross Unrealized Losses Aggregated by Category and Length of Time

Information pertaining to securities available-for-sale with gross unrealized losses aggregated by category and length of time the securities have been in a continuous loss position was as follows:

	Unrealized loss analysis
	Losses < 12 Months				Losses > 12 Months
(In thousands)	Estimated Fair Value		Gross Unrealized Losses		Estimated Fair Value		Gross Unrealized Losses
March 31, 2019
U.S. Treasury securities	$	—	$	—	$	97,566	$	2,806
Obligations of U.S. government agencies		13,670		61		18,692		166
Mortgage-backed securities		62,725		393		480,197		9,295
Obligations of states and municipal subdivisions		—		—		98,577		2,568
Total	$	76,395	$	454	$	695,032	$	14,835

	Unrealized loss analysis
	Losses < 12 Months				Losses > 12 Months
(In thousands)	Estimated Fair Value		Gross Unrealized Losses		Estimated Fair Value		Gross Unrealized Losses
December 31, 2018
U.S. Treasury securities	$	—	$	—	$	96,785	$	3,628
Obligations of U.S. government agencies		25,978		183		10,152		101
Mortgage-backed securities		259,794		2,864		405,974		16,029
Obligations of states and municipal subdivisions		74,503		2,501		125,092		10,611
Total	$	360,275	$	5,548	$	638,003	$	30,369