Asset Retirement Obligations (Tables)

3 Months Ended

Mar. 31, 2013

Asset Retirement Obligations [Abstract]

Changes In Asset Retirement Obligation Liability

Asset retirement obligation as of January 1, 2013	$	44,696
Additional obligations		867
Accretion expense		660
Change in estimates		(5,245)
Payments		(621)
Foreign currency translation adjustments		(1,146)
Asset retirement obligation as of March 31, 2013	$	39,211