Consolidation and Nature of Operations (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014
Cash paid (received) during the period for:
Income taxes, net of refunds	$ 2,692	$ (131,154)
Interest, net of amounts capitalized	143,116	145,285
Significant non-cash investing and financing activities:
Accrued capital expenditures	$ 36,718	$ 24,135