Accrued Expenses (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2012	Dec. 31, 2011
Payables and Accruals [Abstract]
Payroll and benefits	$ 56,657	$ 59,928
Customer advances and deferred revenue	40,877	34,672
Accrued interest	28,271	11,941
Income taxes payable	7,483	4,446
Accrued severance plan obligations (Note 13)	7,224	7,476
Other accrued expenses	33,060	39,824
Total accrued expenses	$ 173,572	$ 158,287