|
Contingencies (Details) (USD $)
In Millions, unless otherwise specified |
Mar. 31, 2015
|
|---|---|
| Wexpro [Member] | |
| Loss Contingencies [Line Items] | |
| Overriding royalty interest | 4.00% |
| Loss Contingency, Range of Possible Loss, Maximum | $ 14.1 |
| Unaffiliated Entity [Member] | |
| Loss Contingencies [Line Items] | |
| Loss Contingency, Range of Possible Loss, Maximum | $ 16.2 |