Impairment of Investment Securities (Tables)

3 Months Ended

Mar. 31, 2018

Impairment of Investment Securities Disclosure [Abstract]

Schedule of Unrealized Losses and Estimated Fair Values

The following table presents the gross unrealized losses and estimated fair values at December 31, 2017 by investment category and time frame for which securities have been in a continuous unrealized loss position:



	Less Than 12 Months					12 Months or More					Total
	Estimated Fair Value		Gross Unrealized Losses			Estimated Fair Value		Gross Unrealized Losses			Estimated Fair Value		Gross Unrealized Losses
	(dollars in thousands)
Obligations of U.S. Government Agencies:
Mortgage-Backed Securities – Residential	$	5,584	$	(21	)	$	—	$	—		$	5,584	$	(21	)
Mortgage-Backed Securities - Commercial	48,322		(962		)	32,683		(894		)	81,005		(1,856		)
Obligations of U.S. Government-Sponsored Enterprises:
Mortgage-Backed Securities – Residential	351,222		(2,295		)	400,984		(9,746		)	752,206		(12,041		)
Mortgage-Backed Securities – Commercial	13,985		(71		)	—		—			13,985		(71		)
Other Government-Sponsored Enterprises	997		(1		)	99		—			1,096		(1		)
Obligation of States and Political Subdivisions	7,144		(32		)	3,653		(129		)	10,797		(161		)
Corporate Securities	3,993		(4		)	—		—			3,993		(4		)
Pooled Trust Preferred Collateralized Debt Obligations	—		—			19,120		(4,379		)	19,120		(4,379		)
Total Securities	$	431,247	$	(3,386	)	$	456,539	$	(15,148	)	$	887,786	$	(18,534	)

The following table presents the gross unrealized losses and estimated fair values at March 31, 2018 for both available for sale and held to maturity securities by investment category and time frame for which securities have been in a continuous unrealized loss position:



	Less Than 12 Months					12 Months or More					Total
	Estimated Fair Value		Gross Unrealized Losses			Estimated Fair Value		Gross Unrealized Losses			Estimated Fair Value		Gross Unrealized Losses
	(dollars in thousands)
Obligations of U.S. Government Agencies:
Mortgage-Backed Securities – Residential	$	7,923	$	(190	)	$	—	$	—		$	7,923	$	(190	)
Mortgage-Backed Securities – Commercial	95,862		(2,120		)	31,813		(1,356		)	127,675		(3,476		)
Obligations of U.S. Government-Sponsored Enterprises:
Mortgage-Backed Securities – Residential	500,625		(10,277		)	378,709		(15,836		)	879,334		(26,113		)
Mortgage-Backed Securities – Commercial	13,560		(299		)	—		—			13,560		(299		)
Other Government-Sponsored Enterprises	999		(1		)	99		(1		)	1,098		(2		)
Obligations of States and Political Subdivisions	31,032		(413		)	3,489		(293		)	34,521		(706		)
Debt securities issued by foreign governments	197		(3		)	—		—			197		(3		)
Corporate Securities	18,764		(214		)	—		—			18,764		(214		)
Pooled Trust Preferred Collateralized Debt Obligations	—		—			6,362		(722		)	6,362		(722		)
Total Securities	$	668,962	$	(13,517	)	$	420,472	$	(18,208	)	$	1,089,434	$	(31,725	)

Pooled Trust Preferred Collateralized Debt Obligations

The following table provides information related to our pooled trust preferred collateralized debt obligations as of March 31, 2018:



Deal	Class	Book Value		Estimated Fair Value		Unrealized Gain (Loss)			Moody’s/ Fitch Ratings	Number of Banks	Deferrals and Defaults as a % of Current Collateral		Excess Subordination as a % of Current Performing Collateral
(dollars in thousands)
Pre TSL IV	Mezzanine	$	933	$	738	$	(195	)	Ba1/BB	5	—	%	113.79	%
Pre TSL VIII	Mezzanine	2,072		2,295		223			C/C	26	38.52		0.00
Pre TSL IX	Mezzanine	2,457		3,000		543			B1/C	37	27.83		19.46
Pre TSL X	Mezzanine	1,894		2,301		407			Caa1/C	41	26.29		1.73
Pre TSL XII	Mezzanine	6,151		5,624		(527		)	B3/C	64	23.39		0.00
MMCap I	Mezzanine	95		174		79			Ca/C	7	69.35		69.99
Total		$	13,602	$	14,132	$	530

Cumulative Roll Forward of Credit Losses Recognized in Earnings for Debt Securities held and not Intended to be Sold

The following table provides a cumulative roll forward of credit losses recognized in earnings for debt securities held and not intended to be sold:



	For the Three Months Ended March 31,
	2018			2017
	(dollars in thousands)
Balance, beginning (a)	$	12,208		$	17,056
Credit losses on debt securities for which other-than-temporary impairment was not previously recognized	—			—
Additional credit losses on debt securities for which other-than-temporary impairment was previously recognized	—			—
Increases in cash flows expected to be collected, recognized over the remaining life of the security (b)	(147		)	(228		)
Reduction for debt securities called during the period	(2,302		)	—
Balance, ending	$	9,759		$	16,828


(a)	The beginning balance represents credit related losses included in other-than-temporary impairment charges recognized on debt securities in prior periods.


(b)	Represents the increase in cash flows recognized in interest income during the period.