Investment Securities (Tables)

3 Months Ended

Mar. 31, 2017

Investments, Debt and Equity Securities [Abstract]

Summary of Amortized Cost and Estimated Fair Value of Investment Securities

The majority of securities held are traded in markets where similar assets are actively traded. Estimated fair values were obtained from an independent pricing service based upon market quotes.

	March 31, 2017
	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	$	1,749	$	1	$	-		$	1,750		0.08	%
Residential mortgage-backed securities		1,848,307		19,131		(5,685	)		1,861,753		81.95	%
CMO/REMIC - residential		324,283		3,403		(1,242	)		326,444		14.37	%
Municipal bonds		75,886		716		(881	)		75,721		3.33	%
Other securities		5,679		356		-			6,035		0.27	%
Total available-for-sale securities	$	2,255,904	$	23,607	$	(7,808	)	$	2,271,703		100.00	%
Investment securities held-to-maturity:
Government agency/GSE	$	176,281	$	751	$	(1,620	)	$	175,412		19.92	%
Residential mortgage-backed securities		186,480		-		(1,528	)		184,952		21.07	%
CMO		238,397		-		(7,563	)		230,834		26.93	%
Municipal bonds		283,899		1,210		(4,552	)		280,557		32.08	%
Total held-to-maturity securities	$	885,057	$	1,961	$	(15,263	)	$	871,755		100.00	%
	December 31, 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	$	2,750	$	2	$	-		$	2,752		0.12	%
Residential mortgage-backed securities		1,822,168		18,812		(6,232	)		1,834,748		80.81	%
CMO/REMIC - residential		345,313		3,361		(1,485	)		347,189		15.29	%
Municipal bonds		80,137		889		(955	)		80,071		3.53	%
Other securities		5,506		200		-			5,706		0.25	%
Total available-for-sale securities	$	2,255,874	$	23,264	$	(8,672	)	$	2,270,466		100.00	%
Investment securities held-to-maturity:
Government agency/GSE	$	182,648	$	362	$	(1,972	)	$	181,038		20.03	%
Residential mortgage-backed securities		193,699		-		(1,892	)		191,807		21.25	%
CMO		244,419		-		(6,808	)		237,611		26.81	%
Municipal bonds		290,910		776		(4,768	)		286,918		31.91	%
Total held-to-maturity securities	$	911,676	$	1,138	$	(15,440	)	$	897,374		100.00	%

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 March 31,
	2017		2016
	(Dollars in thousands)
Investment securities available-for-sale:
Taxable	$	11,926	$	11,380
Tax-advantaged		714		1,419
Total interest income from available-for-sale securities		12,640		12,799
Investment securities held-to-maturity:
Taxable		3,277		2,620
Tax-advantaged		2,230		2,728
Total interest income from held-to-maturity securities		5,507		5,348
Total interest income from investment securities	$	18,147	$	18,147

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 March 31, 2017 and December 31, 2016. Management has reviewed individual securities to determine whether a decline in fair value below the amortized cost basis is other-than-temporary. The unrealized losses on these securities were primarily attributed to changes in interest rates. The issuers of these securities have not, to our knowledge, evidenced any cause for default on these securities. These securities have fluctuated in value since their purchase dates as market rates have fluctuated. However, we have the ability and the intention to hold these securities until their fair values recover to cost or maturity. As such, management does not deem these securities to be Other-Than-Temporarily-Impaired (“OTTI”).

	March 31, 2017
	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		498,198		(5,685	)		-		-			498,198		(5,685	)
CMO/REMIC - residential		97,275		(1,242	)		-		-			97,275		(1,242	)
Municipal bonds		23,231		(880	)		5,986		(1	)		29,217		(881	)
Total available-for-sale securities	$	618,704	$	(7,807	)	$	5,986	$	(1	)	$	624,690	$	(7,808	)
Investment securities held-to-maturity:
Government agency/GSE	$	46,205	$	(1,620	)	$	-	$	-		$	46,205	$	(1,620	)
Residential mortgage-backed securities		184,952		(1,528	)		-		-			184,952		(1,528	)
CMO		230,834		(7,563	)		-		-			230,834		(7,563	)
Municipal bonds		110,334		(3,491	)		33,200		(1,061	)		143,534		(4,552	)
Total held-to-maturity securities	$	572,325	$	(14,202	)	$	33,200	$	(1,061	)	$	605,525	$	(15,263	)

	December 31, 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		583,143		(6,232	)		-		-			583,143		(6,232	)
CMO/REMIC - residential		128,595		(1,485	)		-		-			128,595		(1,485	)
Municipal bonds		23,255		(954	)		5,981		(1	)		29,236		(955	)
Total available-for-sale securities	$	734,993	$	(8,671	)	$	5,981	$	(1	)	$	740,974	$	(8,672	)
Investment securities held-to-maturity:
Government agency/GSE	$	76,854	$	(1,972	)	$	-	$	-		$	76,854	$	(1,972	)
Residential mortgage-backed securities		191,807		(1,892	)		-		-			191,807		(1,892	)
CMO		237,611		(6,808	)		-		-			237,611		(6,808	)
Municipal bonds		145,804		(3,711	)		36,971		(1,057	)		182,775		(4,768	)
Total held-to-maturity securities	$	652,076	$	(14,383	)	$	36,971	$	(1,057	)	$	689,047	$	(15,440	)

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

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

	March 31, 2017
	Avaliable-for-sale				Held-to-maturity
	Amortized		Fair		Amortized		Fair
	Cost		Value		Cost		Value
	(Dollars in thousands)
Due in one year or less	$	22,498	$	22,719	$	424	$	424
Due after one year through five years		1,848,800		1,867,464		165,814		162,958
Due after five years through ten years		327,338		323,905		312,610		308,128
Due after ten years		57,268		57,615		406,209		400,245
Total investment securities	$	2,255,904	$	2,271,703	$	885,057	$	871,755