Employee Benefit Plans - Components of Net Periodic Benefit Cost (Detail) (USD $)	9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012
Defined Benefit Pension Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost		$ 190,714
Interest cost	107,444	133,724
Expected return on plan assets	(160,996)	(241,398)
Amortization of unrecognized prior service cost		(40,472)
Amortization of unrecognized net loss	67,309	53,580
Remaining amortization of unrecognized net loss due to settlements	62,280	168,580
Net gain due to curtailment		(291,413)
Amortization of transition obligation
Net periodic benefit cost	76,037	(26,685)
Post Retirement Benefit Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	17,213	19,501
Interest cost	22,430	22,468
Expected return on plan assets
Amortization of unrecognized prior service cost
Amortization of unrecognized net loss	3,372	2,206
Remaining amortization of unrecognized net loss due to settlements
Net gain due to curtailment
Amortization of transition obligation	2,185	2,185
Net periodic benefit cost	$ 45,200	$ 46,360