Business Segments and Geographic Information (Details 1) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Pre-Tax Income Reconciliation of Segments
Total operating income from segments	$ 89,037	$ 78,750	$ 166,109	$ 152,049
Unallocated Amount:
General and Administrative Expenses	(28,148)	(27,363)	(56,650)	(59,403)
Net Interest Expense	(19,778)	(19,938)	(39,698)	(38,095)
Loss on extinguishment of debt	0	(5,527)	0	(5,527)
Income before income taxes and equity in earnings of affiliates	$ 41,111	$ 25,922	$ 69,761	$ 49,024