Stock Appreciation Rights Activity (Detail) (Stock Appreciation Rights (SARs), USD $)	1 Months Ended		12 Months Ended
	Nov. 30, 2012	Aug. 31, 2012	Dec. 31, 2013	Dec. 31, 2012
Stock Appreciation Rights (SARs)
Stock Appreciation Rights Shares
Shares, Outstanding at beginning of year			170,000
Granted	100,000	70,000		170,000
Shares, Outstanding at end of year			170,000	170,000
Exercisable at end of year end			50,416
Vested at December 31, 2013 and expected to vest			170,000
Weighted Average Exercise Price
Weighted Average Exercise Price per Share, Outstanding at beginning of year			18.18
Granted				18.18
Weighted Average Exercise Price per Share, Outstanding at end of year			18.18	18.18
Exercisable at end of year end			$ 17.48
Vested at December 31 and expected to vest			$ 18.18
Stock Appreciation Rights Aggregate Intrinsic Value
Stock Appreciation Rights outstanding at end of year			$ 720,300
Exercisable at end of year			240,097
Vested at December 31, 2013 and expected to vest			$ 720,300
Stock Appreciation Rights, Weighted Average Remaining Contractual Life
Stock Appreciation Rights outstanding at end of year			8 years 9 months 4 days
Vested at December 31, 2013 and expected to vest			8 years 9 months 4 days
Exercisable at end of year			8 years 9 months