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Stockholders' Equity - Additional Information (Detail) (USD $)	12 Months Ended			1 Months Ended	0 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Mar. 26, 2014	Jul. 21, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock Issued During Period, Value, Restricted Stock Award, Net of Forfeitures
Stock Repurchase Program, Number of Shares Authorized to be Repurchased	448,500
Share-based Compensation	316,985us-gaap_ShareBasedCompensation	2,962us-gaap_ShareBasedCompensation	60,009us-gaap_ShareBasedCompensation
Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Stock Options	49,544
Subsidiaries [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Amount of Restricted Net Assets for Consolidated and Unconsolidated Subsidiaries	92,300,000
Parent Company [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Amount of Restricted Net Assets for Consolidated and Unconsolidated Subsidiaries	96,500,000
Restricted Investments, Percent of Net Assets	95.70%
2002 Stock Option Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of common shares issued subject to adjustment			300,000
2012 Incentive and Equity Award Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of common shares issued subject to adjustment	500,000
Number of shares granted during period				30,833
Number of shares granted fair value				300,000
2012 Non-Employee Director Stock Award Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of common shares issued subject to adjustment	250,000
2012 Non-Employee Director Stock Award Plan [Member] \| Chief Executive Officer [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock Issued During Period, Value, Restricted Stock Award, Net of Forfeitures					$ 58,200
Stock Issued During Period, Shares, Restricted Stock Award, Net of Forfeitures					5,000