Share Based Compensation - Share Based Compensation Expense (Income) Included in Operating Expense (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Share based and Long Term Incentive Compensation	$ 1,544	$ 3,458
General and administrative expense
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Share based and Long Term Incentive Compensation	1,506	2,122
Other Operating Expenses
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Share based and Long Term Incentive Compensation	$ 38	$ 1,336