Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Statement of Comprehensive Income [Abstract]
Net earnings	$ 751.9	$ 578.6	$ 499.4
Other comprehensive income (loss), net of tax:
Foreign currency translation adjustments (net of tax of $0.0 in 2018, 2017, and 2016)	(19.7)	22.2	(0.9)
Comprehensive income	$ 732.2	$ 600.8	$ 498.5