Consolidated Statements of Comprehensive Income (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract]
Net earnings	$ 42,004	$ 44,182	$ 88,461	$ 96,123
Foreign currency translation adjustments	(2,994)	(3,007)	(1,371)	(31)
Total other comprehensive loss	(2,994)	(3,007)	(1,371)	(31)
COMPREHENSIVE INCOME	$ 39,010	$ 41,175	$ 87,090	$ 96,092