Investment Securities, Part II (Details) (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Available-for-sale Securities, Debt Maturities, Fair Value, Fiscal Year Maturity [Abstract]
One year or less	$ 88,761,000
After 1 through 5 years	124,903,000
After 5 through 10 years	189,639,000
After ten years	2,220,000
Fair Value	405,523,000		377,856,000
Available-for-sale, Weighted Average Yield, Maturities Year One (in hundredths)	1.68%
Available-for-sale , Weighted Average Yield, Maturities After 1 through 5 Years (in hundredths)	2.32%
Available-for-sale, Weighted Average Yield, Maturities After 5 through 10 Years (in hundredths)	2.57%
Available-for-sale , Weighted Average Yield, Maturities After 10 Years (in hundredths)	1.16%
Available-for-sale , Weighted Average Yield, Maturities (in hundredths)	2.29%
Available-for-sale, Full Tax-equivalent Yield, Maturities Year One (in hundredths)	1.86%
Available-for-sale, Full Tax-equivalent Yield, Maturities After 1 through 5 Years (in hundredths)	3.07%
Available-for-sale, Full Tax-equivalent Yield, Maturities After 5 through 10 years (in hundredths)	2.99%
Available-for-sale, Full Tax-equivalent Yield, Maturities After Ten Years (in hundredths)	1.16%
Available-for-sale, Full Tax-equivalent Yield, Maturities (in hundredths)	2.75%
Held-to-maturity Securities, Debt Maturities, Net Carrying Amount [Abstract]
Held-to-maturity Securities	48,799,000		53,650,000
Held To Maturity Weighted Average Yield Maturities Year One	2.24%
Held To Maturity Weighted Average Yield Maturities After 1 Through 5 Years	2.10%
Held To Maturity Weighted Average Yield Maturities After 5 Through 10 Years	2.53%
Held To Maturity Weighted Average Yield Maturities After 10 Years	0.00%
Held To Maturity Weighted Average Yield Maturities	2.24%
Held To Maturity Tax Equivalent Yield Maturities Year One	2.24%
Held To Maturity Tax Equivalent Yield Maturities After 1 Through 5 Years	2.10%
Held To Maturity Tax Equivalent Yield Maturities After 5 Through 10 Years	2.53%
Held To Maturity Tax Equivalent Yield Maturities After 10 Years	0.00%
Held To Maturity Tax Equivalent Yield Maturities	2.24%
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		330,000,000
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Less than 12 months, Fair Value	24,345,000		30,440,000
Less than 12 months, Unrealized Losses	(89,000)		(224,000)
12 months or longer, Fair Value	81,972,000		119,022,000
12 months or longer, Unrealized losses	(1,877,000)		(5,156,000)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	106,317,000		149,462,000
Total Unrealized Losses	1,966,000		5,380,000
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	1,111,000
Additions related to OTTI losses not previously recognized	0	0
Reductions due to sales / (recoveries)	0	0
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
PreTSL XXVIII [Member]
Details of Trust Preferred Securities [Abstract]
Book Value	3,255,000
Market Value	2,166,000
Unrealized Gains (Losses)	(1,089,000)
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	83,489,000
After 1 through 5 years	41,756,000
After 5 through 10 years	0
After ten years	0
Fair Value	125,245,000		99,957,000
Held-to-maturity Securities, Debt Maturities, Net Carrying Amount [Abstract]
Held-to-maturity Securities, Debt Maturities, within One Year, Net Carrying Amount	34,237,000
Held-to-maturity Securities, Debt Maturities, after One Through Five Years, Net Carrying Amount	9,700,000
Held-to-maturity Securities, Debt Maturities, after Five Through Ten Years, Net Carrying Amount	4,862,000
Held-to-maturity Securities, Debt Maturities, after Ten Years, Net Carrying Amount	0
Held-to-maturity Securities	48,799,000		53,650,000
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Less than 12 months, Fair Value	9,999,000		7,289,000
Less than 12 months, Unrealized Losses	(1,000)		(46,000)
12 months or longer, Fair Value	53,802,000		75,030,000
12 months or longer, Unrealized losses	(291,000)		(1,312,000)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	63,801,000		82,319,000
Total Unrealized Losses	292,000		1,358,000
Number of securities in Unrealized Loss Positions	16
Held-to-maturity Securities, Continuous Unrealized Loss Position [Abstract]
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value	0		4,853,000
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Aggregate Loss	0		(12,000)
Held-to-maturity Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value	0		0
Held-to-maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss	0		0
Held-to-maturity Securities, Continuous Unrealized Loss Position, Fair Value	0		4,853,000
Held-to-maturity Securities, Continuous Unrealized Loss Position, Accumulated Loss	0		(12,000)
Obligations of states and political subdivisions
Available-for-sale Securities, Debt Maturities, Fair Value, Fiscal Year Maturity [Abstract]
One year or less	5,260,000
After 1 through 5 years	39,763,000
After 5 through 10 years	35,780,000
After ten years	0
Fair Value	80,803,000		78,084,000
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Less than 12 months, Fair Value	4,283,000		3,586,000
Less than 12 months, Unrealized Losses	(53,000)		(19,000)
12 months or longer, Fair Value	1,206,000		4,416,000
12 months or longer, Unrealized losses	(30,000)		(94,000)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	5,489,000		8,002,000
Total Unrealized Losses	83,000		113,000
Number of securities in Unrealized Loss Positions	2		10
Mortgage-backed securities: GSE residential
Available-for-sale Securities, Debt Maturities, Fair Value, Fiscal Year Maturity [Abstract]
One year or less	12,000
After 1 through 5 years	41,396,000
After 5 through 10 years	151,842,000
After ten years	0
Fair Value	193,250,000		195,401,000
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Less than 12 months, Fair Value	10,063,000		19,565,000
Less than 12 months, Unrealized Losses	(35,000)		(159,000)
12 months or longer, Fair Value	22,810,000		37,224,000
12 months or longer, Unrealized losses	(455,000)		(802,000)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	32,873,000		56,789,000
Total Unrealized Losses	490,000		961,000
Number of securities in Unrealized Loss Positions	7		11
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	2,166,000
Fair Value	2,166,000		364,000
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	2,166,000		364,000
12 months or longer, Unrealized losses	(1,089,000)		(2,936,000)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	2,166,000		364,000
Total Unrealized Losses	1,089,000		2,936,000
Number of securities in Unrealized Loss Positions	1		1
Other securities
Available-for-sale Securities, Debt Maturities, Fair Value, Fiscal Year Maturity [Abstract]
One year or less	0
After 1 through 5 years	1,988,000
After 5 through 10 years	2,017,000
After ten years	54,000
Fair Value	4,059,000		4,050,000
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	1,988,000		1,988,000
12 months or longer, Unrealized losses	(12,000)		(12,000)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	1,988,000		1,988,000
Total Unrealized Losses	$ 12,000		$ 12,000
Number of securities in Unrealized Loss Positions	1