Investment Securities (Tables)

6 Months Ended

Jun. 30, 2016

Investments, Debt and Equity Securities [Abstract]

Summary of Amortized Cost and Estimated Fair Value of Investment Securities

The majority of securities held are publicly traded, and the estimated fair values were obtained from an independent pricing service based upon market quotes.

	June 30, 2016
	Amortized Cost		Gross Unrealized Holding Gain		Gross Unrealized Holding Loss		Fair Value		Total Percent
			(Dollars in thousands)
Investment securities available-for-sale:
Government agency/GSE	$	4,750	$	13	$	-	$	4,763		0.21%
Residential mortgage-backed securities		1,663,091		54,359		-		1,717,450		76.40%
CMO/REMIC - residential		388,881		9,015		-		397,896		17.70%
Municipal bonds		119,756		2,893		(1)		122,648		5.46%
Other securities		5,000		275		-		5,275		0.23%
Total available-for-sale  securities	$	2,181,478	$	66,555	$	(1)	$	2,248,032		100.00%
Investment securities held-to-maturity (1):
Government agency/GSE	$	209,301	$	6,336	$	-	$	215,637		28.90%
Residential mortgage-backed securities		215,762		6,274		-		222,036		29.79%
CMO		974		501		-		1,475		0.13%
Municipal bonds		298,320		6,983		(970)		304,333		41.18%
Total held-to-maturity  securities	$	724,357	$	20,094	$	(970)	$	743,481		100.00%
	December 31, 2015
	Amortized Cost		Gross Unrealized Holding Gain		Gross Unrealized Holding Loss		Fair Value		Total Percent
			(Dollars in thousands)
Investment securities available-for-sale:
Government agency/GSE	$	5,752	$	-	$	(7)	$	5,745		0.24%
Residential mortgage-backed securities		1,788,857		26,001		(1,761)		1,813,097		76.55%
CMO/REMIC - residential		380,166		4,689		(1,074)		383,781		16.20%
Municipal bonds		157,940		3,036		(3)		160,973		6.80%
Other securities		5,000		50		-		5,050		0.21%
Total available-for-sale securities	$	2,337,715	$	33,776	$	(2,845)	$	2,368,646		100.00%
Investment securities held-to-maturity (1):
Government agency/GSE	$	293,338	$	1,176	$	(734)	$	293,780		34.47%
Residential mortgage-backed securities		232,053		-		(1,293)		230,760		27.27%
CMO		1,284		569		-		1,853		0.15%
Municipal bonds		324,314		3,051		(719)		326,646		38.11%
Total held-to-maturity  securities	$	850,989	$	4,796	$	(2,746)	$	853,039		100.00%

(1) Securities held-to-maturity are presented in the condensed consolidated balance sheets at amortized cost.

Summary of Interest Income Earned on Investment Securities

The following table provides information about the amount of interest income earned on investment securities which is fully taxable and which is exempt from regular federal income tax.

	For the Three Months Ended June 30,				For the Six Months Ended June 30,
	2016		2015		2016		2015
	(Dollars in thousands)
Investment securities available-for-sale:
Taxable	$	10,827	$	12,784	$	22,207	$	25,707
Tax-advantaged		1,191		4,719		2,610		9,730
Investment securities held-to-maturity:
Taxable		2,215		36		4,835		74
Tax-advantaged		2,528		-		5,256		-
Total interest income from investment securities	$	16,761	$	17,539	$	34,908	$	35,511

Summary of Continuous Unrealized Loss Position of Securities

The tables below show the Company’s investment securities’ gross unrealized losses and fair value by investment category and length of time that individual securities have been in a continuous unrealized loss position at June 30, 2016 and December 31, 2015. Management has reviewed individual securities to determine whether a decline in fair value below the amortized cost basis is other-than-temporary.

	June 30, 2016
	Less Than 12 Months				12 Months or Longer				Total
	Fair Value		Gross Unrealized Holding Losses		Fair Value		Gross Unrealized Holding Losses		Fair Value		Gross Unrealized Holding Losses
	(Dollars in thousands)
Investment securities available-for-sale:
Government agency/GSE	$	-	$	-	$	-	$	-	$	-	$	-
Residential mortgage-backed securities		-		-		-		-		-		-
CMO/REMIC - residential		-		-		-		-		-		-
Municipal bonds		-		-		5,971		(1)		5,971		(1)
Other securities		-		-		-		-		-		-
Total available-for-sale  securities	$	-	$	-	$	5,971	$	(1)	$	5,971	$	(1)
Investment securities held-to-maturity:
Government agency/GSE	$	-	$	-	$	-	$	-	$	-	$	-
Residential mortgage-backed securities		-		-		-		-		-		-
CMO		-		-		-		-		-		-
Municipal bonds		67,573		(970)		-		-		67,573		(970)
Other securities		-		-		-		-		-		-
Total held-to-maturity securities	$	67,573	$	(970)	$	-	$	-	$	67,573	$	(970)

	December 31, 2015
	Less Than 12 Months				12 Months or Longer				Total
	Fair Value		Gross Unrealized Holding Losses		Fair Value		Gross Unrealized Holding Losses		Fair Value		Gross Unrealized Holding Losses
	(Dollars in thousands)
Investment securities available-for-sale:
Government agency/GSE	$	5,745	$	(7)	$	-	$	-	$	5,745	$	(7)
Residential mortgage-backed securities		437,699		(1,761)		-		-		437,699		(1,761)
CMO/REMIC - residential		171,923		(1,074)		-		-		171,923		(1,074)
Municipal bonds		398		(2)		5,961		(1)		6,359		(3)
Other securities		-		-		-		-		-		-
Total available-for-sale securities	$	615,765	$	(2,844)	$	5,961	$	(1)	$	621,726	$	(2,845)
Investment securities held-to-maturity:
Government agency/GSE	$	84,495	$	(734)	$	-	$	-	$	84,495	$	(734)
Residential mortgage-backed securities		230,760		(1,293)		-		-		230,760		(1,293)
CMO		-		-		-		-		-		-
Municipal bonds		110,119		(719)		-		-		110,119		(719)
Other securities		-		-		-		-		-		-
Total held-to-maturity securities	$	425,374	$	(2,746)	$	-	$	-	$	425,374	$	(2,746)

Summary of Amortized Cost and Fair Value of Debt Securities by Contractual Maturity

Mortgage-backed securities and CMO/REMIC are included in maturity categories based upon estimated prepayment speeds.

	June 30, 2016
	Available-for-sale				Held-to-maturity
	Amortized Cost		Fair Value		Amortized Cost		Fair Value
	(Dollars in thousands)
Due in one year or less	$	12,202	$	12,343	$	-	$	-
Due after one year through five years		1,795,806		1,851,485		167,856		171,966
Due after five years through ten years		131,286		134,700		240,842		245,295
Due after ten years		242,184		249,504		315,659		326,220
Total investment securities	$	2,181,478	$	2,248,032	$	724,357	$	743,481