Fixed Assets Depreciation Expense (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Fixed Assets And Asset Retirement Obligations [Abstract]
Depreciation expense	$ 33,716	$ 20,736	$ 78,265	$ 52,422