Quarterly report pursuant to Section 13 or 15(d)

Commitments and Contingencies (Firm Transportation Commitments) (Details)

v3.7.0.1
Commitments and Contingencies (Firm Transportation Commitments) (Details)
$ in Thousands
Mar. 31, 2017
USD ($)
MMBTU / d
Other Commitments [Line Items]  
Firm sale contracts (in MMBtu's) | MMBTU / d 2,952,375
Long-term Commitment (Excluding Unconditional Purchase Obligation) [Abstract]  
Remaining 2017 | MMBTU / d 725,625
2018 | MMBTU / d 457,000
2019 | MMBTU / d 604,750
2020 | MMBTU / d 518,000
2021 | MMBTU / d 371,000
Thereafter | MMBTU / d 276,000
Total | MMBTU / d 2,952,375
Purchase commitment  
Other Commitments [Abstract]  
2018 $ 39,330
Total 78,660
Transportation commitment  
Other Commitments [Abstract]  
Remaining 2017 143,816
2018 241,709
2019 241,708
2020 240,746
2021 239,786
Thereafter 2,705,270
Total $ 3,813,035