CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Unaudited) (Parenthetical) (USD $)	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
OTHER COMPREHENSIVE INCOME (LOSS)
Change in unrealized holding gains on investment securities, deferred income tax expense	$ 3,698,356	$ 6,473,538
Reclassification adjustment for realized investment (gains) losses included in net income (loss), income tax (expense) benefit	(933,755)	(3,121,415)
Reclassification adjustment for amounts amortized into net periodic pension and postretirement benefit cost, deferred income tax expense	$ 188,746	$ 233,991