Condensed Consolidated Statements of Comprehensive Income (unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Condensed Consolidated Statements of Comprehensive Income (unaudited) [Abstract]
Net earnings	$ 179,556	$ 158,069	$ 337,627	$ 309,485
Other comprehensive income/(loss), net of tax:
Foreign currency translation adjustments	49,515	(46,470)	79,927	(44,727)
Total other comprehensive income/(loss), net of tax	49,515	(46,470)	79,927	(44,727)
Comprehensive income	$ 229,071	$ 111,599	$ 417,554	$ 264,758