Investment Securities, Part II (Details) (USD $)	9 Months Ended
	Sep. 30, 2014 securities	Sep. 30, 2013	Dec. 31, 2013
Available-for-sale Securities, Debt Maturities, Fair Value, Fiscal Year Maturity [Abstract]
One year or less	$ 74,718,000
After 1 through 5 years	185,734,000
After 5 through 10 years	113,984,000
After ten years	1,196,000
Fair Value	375,632,000		488,724,000
Available-for-sale, Weighted Average Yield, Maturities Year One (in hundredths)	1.62%
Available-for-sale , Weighted Average Yield, Maturities After 1 through 5 Years (in hundredths)	2.49%
Available-for-sale, Weighted Average Yield, Maturities After 5 through 10 Years (in hundredths)	2.69%
Available-for-sale , Weighted Average Yield, Maturities After 10 Years (in hundredths)	1.47%
Available-for-sale , Weighted Average Yield, Maturities (in hundredths)	2.36%
Available-for-sale, Full Tax-equivalent Yield, Maturities Year One (in hundredths)	1.80%
Available-for-sale, Full Tax-equivalent Yield, Maturities After 1 through 5 Years (in hundredths)	2.96%
Available-for-sale, Full Tax-equivalent Yield, Maturities After 5 through 10 years (in hundredths)	3.44%
Available-for-sale, Full Tax-equivalent Yield, Maturities After Ten Years (in hundredths)	1.88%
Available-for-sale, Full Tax-equivalent Yield, Maturities (in hundredths)	2.86%
Held-to-maturity Securities, Debt Maturities, Net Carrying Amount [Abstract]
Held-to-maturity Securities	53,594,000		0
Held To Maturity Weighted Average Yield Maturities Year One	2.21%
Held To Maturity Weighted Average Yield Maturities After 1 Through 5 Years	0.00%
Held To Maturity Weighted Average Yield Maturities After 5 Through 10 Years	2.28%
Held To Maturity Weighted Average Yield Maturities After 10 Years	0.00%
Held To Maturity Weighted Average Yield Maturities	2.22%
Held To Maturity Tax Equivalent Yield Maturities Year One	2.21%
Held To Maturity Tax Equivalent Yield Maturities After 1 Through 5 Years	0.00%
Held To Maturity Tax Equivalent Yield Maturities After 5 Through 10 Years	2.28%
Held To Maturity Tax Equivalent Yield Maturities After 10 Years	0.00%
Held To Maturity Tax Equivalent Yield Maturities	2.22%
Tax rate used to calculate tax-equivalent yields (in hundredths)	35.00%
Percentage investment book value exceeds total stockholders' equity (in hundredths)	10.00%
Investment Securities Pledged as Collateral	300,000,000		321,000,000
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Less than 12 months, Fair Value	45,185,000		348,118,000
Less than 12 months, Unrealized Losses	(401,000)		(13,624,000)
12 months or longer, Fair Value	170,176,000		1,012,000
12 months or longer, Unrealized losses	(6,633,000)		(3,526,000)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	215,361,000		349,130,000
Total Unrealized Losses	7,034,000		17,150,000
Details of Trust Preferred Securities [Abstract]
Coupon Rate of Trust Preferred Security	floating rate coupon of 3-month LIBOR plus 90 basis points
Number of Ratios Utilized in OTTI Credit Model	29
OTTI Cash Flow Initial Default Rate	2.00%
Period For Initial Default Rate Used In OTTI Analysis	two years
Default Rate Applied For Remainder Of OTTI Analysis	36 basis points
Recovery Rate Used In OTTI Cash Flow Analysis	10.00%
Credit losses on trust preferred securities held [Abstract]
Beginning of period	1,111,000	3,989,000
Additions related to OTTI losses not previously recognized	0	0
Reductions due to sales / (recoveries)	0	(2,878,000)
Reductions due to change in intent or likelihood of sale	0	0
Additions related to increases in previously recognized OTTI losses	0	0
Reductions due to increases in expected cash flows	0	0
End of period	1,111,000	1,111,000
Number Of Trust Preferred Securities Sold	2
PreTSL XXVIII [Member]
Details of Trust Preferred Securities [Abstract]
Book Value	3,449,000
Market Value	462,000
Unrealized Gains (Losses)	(2,987,000)
Other-than- temporary Impairment Recorded To-date	(1,111,000)
U.S. Treasury securities and obligations of U.S. government corporations & agencies
Available-for-sale Securities, Debt Maturities, Fair Value, Fiscal Year Maturity [Abstract]
One year or less	67,756,000
After 1 through 5 years	26,903,000
After 5 through 10 years	0
After ten years	0
Fair Value	94,659,000		190,368,000
Held-to-maturity Securities, Debt Maturities, Net Carrying Amount [Abstract]
Held-to-maturity Securities, Debt Maturities, within One Year, Net Carrying Amount	43,881,000
Held-to-maturity Securities, Debt Maturities, after One Through Five Years, Net Carrying Amount	0
Held-to-maturity Securities, Debt Maturities, after Five Through Ten Years, Net Carrying Amount	9,713,000
Held-to-maturity Securities, Debt Maturities, after Ten Years, Net Carrying Amount	0
Held-to-maturity Securities	53,594,000
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Less than 12 months, Fair Value	0		183,074,000
Less than 12 months, Unrealized Losses	0		(7,574,000)
12 months or longer, Fair Value	81,908,000		0
12 months or longer, Unrealized losses	(1,769,000)		0
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	81,908,000		183,074,000
Total Unrealized Losses	1,769,000		7,574,000
Number of securities in Unrealized Loss Positions	22
Held-to-maturity Securities, Continuous Unrealized Loss Position [Abstract]
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	0
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Aggregate Loss	0
Held-to-maturity Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	43,663,000
Held-to-maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	(205,000)
Held-to-maturity Securities, Continuous Unrealized Loss Position, Fair Value	43,663,000
Held-to-maturity Securities, Continuous Unrealized Loss Position, Accumulated Loss	205,000
Held-to-maturity, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions	5
Obligations of states and political subdivisions
Available-for-sale Securities, Debt Maturities, Fair Value, Fiscal Year Maturity [Abstract]
One year or less	4,264,000
After 1 through 5 years	33,946,000
After 5 through 10 years	36,110,000
After ten years	676,000
Fair Value	74,996,000		64,562,000
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Less than 12 months, Fair Value	2,464,000		29,986,000
Less than 12 months, Unrealized Losses	(10,000)		(1,708,000)
12 months or longer, Fair Value	9,163,000		808,000
12 months or longer, Unrealized losses	(179,000)		(65,000)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	11,627,000		30,794,000
Total Unrealized Losses	189,000		1,773,000
Number of securities in Unrealized Loss Positions	20		2
Mortgage-backed securities: GSE residential
Available-for-sale Securities, Debt Maturities, Fair Value, Fiscal Year Maturity [Abstract]
One year or less	2,698,000
After 1 through 5 years	124,885,000
After 5 through 10 years	73,876,000
After ten years	0
Fair Value	201,459,000		227,601,000
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Less than 12 months, Fair Value	42,721,000		131,125,000
Less than 12 months, Unrealized Losses	(391,000)		(4,275,000)
12 months or longer, Fair Value	76,664,000		13,000
12 months or longer, Unrealized losses	(1,677,000)		0
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	119,385,000		131,138,000
Total Unrealized Losses	2,068,000		4,275,000
Number of securities in Unrealized Loss Positions	19
Trust preferred securities
Available-for-sale Securities, Debt Maturities, Fair Value, Fiscal Year Maturity [Abstract]
One year or less	0
After 1 through 5 years	0
After 5 through 10 years	0
After ten years	462,000
Fair Value	462,000		191,000
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Less than 12 months, Fair Value	0		0
Less than 12 months, Unrealized Losses	0		0
12 months or longer, Fair Value	462,000		191,000
12 months or longer, Unrealized losses	(2,987,000)		(3,461,000)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	462,000		191,000
Total Unrealized Losses	2,987,000		3,461,000
Number of securities in Unrealized Loss Positions	1		1
Credit losses on trust preferred securities held [Abstract]
Available-for-sale Securities, Gross Realized Gains (Losses), Sale Proceeds	1,400,000
Other securities
Available-for-sale Securities, Debt Maturities, Fair Value, Fiscal Year Maturity [Abstract]
One year or less	0
After 1 through 5 years	0
After 5 through 10 years	3,998,000
After ten years	58,000
Fair Value	4,056,000		6,002,000
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Less than 12 months, Fair Value	0		3,933,000
Less than 12 months, Unrealized Losses	0		(67,000)
12 months or longer, Fair Value	1,979,000		0
12 months or longer, Unrealized losses	(21,000)		0
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	1,979,000		3,933,000
Total Unrealized Losses	$ 21,000		$ 67,000
Number of securities in Unrealized Loss Positions	1