Significant Commitments by Category (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014
Minimum Rental Commitments
2015	$ 1,967
2016	1,873
2017	1,293
2018	675
2019	674
Thereafter	0
Total	6,482
Drilling Commitments
Commitments
2015	33,660
2016	0
2017	0
2018	0
2019	0
Thereafter	0
Total	33,660
Firm Transportation Commitments
Commitments
2015	2,002
2016	1,095
2017	1,095
2018	1,095
2019	1,095
Thereafter	9,672
Total	16,054
Other Commitments
Commitments
2015	10,337
2016	19,057
2017	13,842
2018	13,688
2019	13,688
Thereafter	68,512
Total	$ 139,124

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Contractual Commitments Future Minimum Payments Due In Five Years

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Contractual Commitments Future Minimum Payments Due In Four Years

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Contractual Commitments Future Minimum Payments Due In Three Years

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Contractual Commitments Future Minimum Payments Due In Two Years

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Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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