INVESTMENTS IN DEBT AND EQUITY SECURITIES (Tables)

6 Months Ended

Jun. 30, 2015

Investments, Debt and Equity Securities [Abstract]

Schedule of Available For Sale and Held To Maturity Securities [Table Text Block]

The amortized cost, gross unrealized gains and losses and fair value of investment securities available for sale and held to maturity at June 30, 2015 and December 31, 2014 were as follows:

(dollars in thousands)	Amortized Cost		Gross Unrealized Gains	Gross Unrealized Losses		Fair Value
June 30, 2015:
Available for sale:
U.S. Government sponsored agencies	$	231,379	1,842	(1,238	)	231,983
Residential mortgage-backed	936,625		14,603	(2,823	)	948,405
Commercial mortgage-backed	18,469		56	(2	)	18,523
State and political subdivisions	29,167		18	(292	)	28,893
Corporate notes	270,868		1,925	(1,050	)	271,743
Equity investments	2,000		—	(44	)	1,956
Total	$	1,488,508	18,444	(5,449	)	1,501,503
Held to maturity:
U.S. Government sponsored agencies	$	9,157	30	—		9,187
Residential mortgage-backed	573,237		2,167	(5,637	)	569,767
State and political subdivisions	4,806		1	(91	)	4,716
Total	$	587,200	2,198	(5,728	)	583,670
December 31, 2014:
Available for sale:
U.S. Government sponsored agencies	$	230,159	2,129	(557	)	231,731
Residential mortgage-backed	999,772		14,189	(6,117	)	1,007,844
Commercial mortgage-backed	779		58	—		837
State and political subdivisions	29,805		33	(223	)	29,615
Corporate notes	171,331		2,759	(395	)	173,695
Equity investments	2,000		—	(33	)	1,967
Total	$	1,433,846	19,168	(7,325	)	1,445,689
Held to maturity:
U.S. Government sponsored agencies	$	10,725	42	—		10,767
Residential mortgage-backed	605,077		1,931	(5,782	)	601,226
State and political subdivisions	2,346		1	(68	)	2,279
Total	$	618,148	1,974	(5,850	)	614,272

Investments Classified by Contractual Maturity Date [Table Text Block]

The amortized cost and fair value of debt securities available for sale and held to maturity by contractual maturity at June 30, 2015 are shown in the table below. Securities not due at a single maturity date are shown separately. Expected maturities may differ from contractual maturities if borrowers have the right to call or prepay obligations with or without call or prepayment penalties. The weighted average yields are based on amortized cost.

(dollars in thousands)	Amortized Cost		Fair Value	Weighted Average Yield
June 30, 2015:
Available for sale securities:
Within one year	$	62,932	63,546	2.50	%
After one year through five years	135,179		136,799	1.84
After five years through ten years	191,741		193,981	2.77
After ten years	1,096,656		1,105,221	2.20
Equity investments	2,000		1,956	2.18
Total	$	1,488,508	1,501,503	2.24
Held to maturity securities:
Within one year	$	565	565	3.07	%
After one year through five years	101,555		102,154	1.93
After five years through ten years	56,000		54,759	1.18
After ten years	429,080		426,192	2.09
Total	$	587,200	583,670	1.97

Schedule of Realized Gain (Loss) [Table Text Block]

Gross realized gains and gross realized losses on investment securities for the three and six months ended June 30, 2015 and 2014 were as follows:

	Three Months Ended					Six Months Ended
	June 30,					June 30,
(dollars in thousands)	2015			2014		2015		2014
Gross realized gains on sales of available-for-sale securities	$	8,637		—		9,197		2,010
Gross realized losses on sales of available-for-sale securities	(1,479		)	—		(1,996	)	(730	)
Other-than-temporary impairment	—			(1	)	—		(1	)
Net realized gain (loss) on investment securities	$	7,158		(1	)	7,201		1,279
Provision (benefit) for income taxes on net realized gain (loss) on investment securities	$	2,947		—		2,965		527

Schedule of Unrealized Loss on Investments [Table Text Block]

Gross unrealized losses on investment securities and the fair value of the related securities, aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position, at June 30, 2015 and December 31, 2014, were as follows:

	Less Than 12 Months				12 Months or More			Total
(dollars in thousands)	Fair Value		Unrealized Losses		Fair Value	Unrealized Losses		Fair Value	Unrealized Losses
June 30, 2015:
Available for sale:
U.S. Government sponsored agencies	$	87,514	(1,099	)	14,600	(139	)	102,114	(1,238	)
Residential mortgage-backed	194,279		(922	)	85,274	(1,901	)	279,553	(2,823	)
Commercial mortgage-backed	8,803		(2	)	—	—		8,803	(2	)
State and political subdivisions	28,049		(292	)	—	—		28,049	(292	)
Corporate notes	67,295		(1,009	)	4,959	(41	)	72,254	(1,050	)
Equity investments	—		—		1,956	(44	)	1,956	(44	)
Total	$	385,940	(3,324	)	106,789	(2,125	)	492,729	(5,449	)
Held to maturity:
Residential mortgage-backed	$	246,432	(3,277	)	114,765	(2,360	)	361,197	(5,637	)
State and political subdivisions	3,405		(91	)	—	—		3,405	(91	)
Total	$	249,837	(3,368	)	114,765	(2,360	)	364,602	(5,728	)
December 31, 2014:
Available for sale:
U.S. Government sponsored agencies	$	79,207	(427	)	14,600	(130	)	93,807	(557	)
Residential mortgage-backed	204,378		(1,154	)	191,644	(4,963	)	396,022	(6,117	)
State and political subdivisions	28,148		(223	)	—	—		28,148	(223	)
Corporate notes	9,650		(350	)	4,955	(45	)	14,605	(395	)
Equity investments	1,967		(33	)	—	—		1,967	(33	)
Total	$	323,350	(2,187	)	211,199	(5,138	)	534,549	(7,325	)
Held to maturity:
Residential mortgage-backed	$	28,371	(112	)	325,820	(5,670	)	354,191	(5,782	)
State and political subdivisions	641		(3	)	896	(65	)	1,537	(68	)
Total	$	29,012	(115	)	326,716	(5,735	)	355,728	(5,850	)