Long-Term Cash Incentive Plan - Additional Information (Detail) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Long term incentive plan compensation	$ 657	$ 950
Long Term Incentive Plan 2013
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Estimated payments for employee long term incentive plan	5,100
Deferred compensation cash-based arrangements, liability, current and noncurrent	$ 4,500