XML 11 R39.htm IDEA: XBRL DOCUMENT

Obligations under capital lease (Net Assets Under Capital lease Table) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013
Capital Leases, Balance Sheet, Assets by Major Class, Net [Abstract]
Compressor equipment	$ 37,199
Less: Accumulated amortization	(14,676)
Net assets under capital leases	$ 22,523

Property, plant, or equipment held under lease agreements classified as an asset.

The total charge for the use of long-lived depreciable assets subject to a lease meeting the criteria for capitalization.