Stockholders' Equity and Earnings per Common Share (Details) (USD $) Share data in Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Available-for-sale securities [Abstract]
Realized gains on sales of securities			$ 26,000	$ (1,704,000)
Tax effect			9,000	(579,000)
Available-for-sale Securities			17,000	(1,125,000)
Unrealized Gains (Losses) on Securities [Abstract]
Balance at beginning of the period			1,992,000	1,525,000
Net change for the year			(7,235,000)	2,403,000
Balance at end of the period	(5,243,000)	3,928,000	(5,243,000)	3,928,000
Other Comprehensive Income -- AFS to HTM [Abstract]
Balance at beginning of period			0	0
Net change for the quarter			(4,068,000)	0
Balance at end of period	(4,068,000)	0	(4,068,000)	0
Defined Benefit Pension Plans [Abstract]
Balance at beginning of the period			(2,184,000)	(1,875,000)
Net change for the year			0	0
Balance at end of the period	(2,184,000)	(1,875,000)	(2,184,000)	(1,875,000)
Accumulated Other Comprehensive Income (Loss) [Abstract]
Balance at beginning of the period			(191,463)	(349,581)
Net change for the year	(3,080,300)	2,153,604	(11,303,284)	2,403,011
Balance at end of the period	(11,494,747)	2,053,430	(11,494,747)	2,053,430
Other comprehensive income, pretax [Abstract]
Unrealized holding losses arising during the period			(10,988,000)	5,345,000
Realized gains on sales of securities			(26,000)	1,704,000
Net unrealized losses on securities			(10,962,000)	3,641,000
Unrealized loss transferred			(6,232,000)
Amortization			68,000
Net effect of market adjustment on securities transferred to held-to-maturity			(6,164,000)
Total decrease in other comprehensive loss			(17,126,000)	3,641,000
Other comprehensive income tax expense (benefit) [Abstract]
Unrealized holding losses arising during the period			(3,736,000)	1,817,000
Less reclassification adjustment for losses recognized in income			(9,000)	579,000
Net unrealized losses on securities			(3,727,000)	1,238,000
Unrealized loss transferred tax			(2,119,000)
Amortization tax			23,000
Net effect of market adjustment on securities transferred to held-to-maturity			(2,096,000)
Total decrease in other comprehensive loss			(5,823,000)	1,238,000
Other comprehensive income, net-of-tax [Abstract]
Unrealized holding losses arising during the period			(7,252,000)	3,528,000
Less reclassification adjustment for losses recognized in income			(17,000)	1,125,000
Unrealized gains (losses) on securities, net of all adjustments			(7,235,000)	2,403,000
Unrealized loss transferred net			(4,113,000)
Amortization net of tax			45,000
Net effect of market adjustment on securities transferred to held-to-maturity			(4,068,000)
Total decrease in other comprehensive loss			(11,303,000)	2,403,000
Stock Options [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share (in shares)			155
Gain on sale of available-for-sale securities, net [Member]
Available-for-sale securities [Abstract]
Realized gains on sales of securities	(5,000)	620,000	(26,000)	1,704,000
Other comprehensive income, pretax [Abstract]
Realized gains on sales of securities	5,000	(620,000)	26,000	(1,704,000)
Income tax expense [Member]
Available-for-sale securities [Abstract]
Tax effect	(2,000)	211,000	(9,000)	579,000
Other comprehensive income tax expense (benefit) [Abstract]
Less reclassification adjustment for losses recognized in income	2,000	(211,000)	9,000	(579,000)
Net of tax [Member]
Available-for-sale securities [Abstract]
Available-for-sale Securities	(3,000)	409,000	(17,000)	1,125,000
Other comprehensive income, net-of-tax [Abstract]
Less reclassification adjustment for losses recognized in income	$ 3,000	$ (409,000)	$ 17,000	$ (1,125,000)