Commitments and Contingencies - Litigation (Details) - Court of Ouargla Algeria Foreign Currency Controls $ in Millions	1 Months Ended
Mar. 31, 2011 USD ($)
Commitments and Contingencies
Total litigation amount as per judgment at current exchange rates	$ 21.8
Payment of contract amount in foreign currency	7.5
Payment of contract amount in domestic currency	$ 3.2

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

Name:	us-gaap_OtherCommitmentsLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration