|
Commitments and Contingencies - Gross Held-to-Maturity Investments (Detail) (USD $)
In Thousands, unless otherwise specified |
Dec. 31, 2014
|
|---|---|
| Held-to-maturity Securities [Abstract] | |
| Amortized Cost | $ 69,954 |
| Less: Outside working interest owners share | (65,222) |
| U.S. Bank Money Market Cash Equivalent [Member] | |
| Held-to-maturity Securities [Abstract] | |
| Amortized Cost | $ 135,176 |