Accrued Liabilities and Deferred Credits (Tables)

3 Months Ended

Mar. 31, 2013

Accrued Liabilities and Deferred Credits

Accrued liabilities and deferred credits consist of the following:

	March 31, 2013		December 31, 2012
Accrued compensation	$	1,962	$	3,529
Deferred revenue		27,846		27,962
Environmental and insurance liabilities		1,610		1,621
Other accrued liabilities		15,927		9,240
Total accrued liabilities and deferred credits	$	47,345	$	42,352