Accrued Liabilities (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Accrued Liabilities Detail [Table]
Compensation and employee benefits	$ 15,248	$ 12,784
Deferred tax liability	2,388	0
Oil and gas producing liabilities	7,850	15,966
Unearned income	3,318	13,160
Other accrued liabilities	44,450	39,030
Accrued liabilities	$ 73,254	$ 80,940