Commitments and Contingencies (Tables)

12 Months Ended

Dec. 31, 2015

Commitments and Contingencies Disclosure [Abstract]

Minimum commitments for unrecorded unconditional purchase obligations

At December 31, 2015, total minimum commitments from long-term non-cancelable operating leases, drilling rig commitments, seismic purchase obligations, fracturing services obligations, other purchase obligations and transportation and storage service commitments, based on current transportation and storage rates and the foreign currency exchange rates used to convert Canadian dollars and British pounds into United States dollars at December 31, 2015, were as follows (in thousands):

	Total Minimum Commitments
2016	$	1,275,650
2017	994,328
2018	781,299
2019	547,299
2020	431,221
2021 and beyond	900,961
	$	4,930,758