Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	12 Months Ended
	Dec. 29, 2019	Dec. 30, 2018	Dec. 31, 2017
Statement of Comprehensive Income [Abstract]
Net earnings	$ 112.4	$ 22.9	$ 71.6
Other comprehensive income (loss), net of tax:
Foreign currency translation adjustments, net of tax benefit of $0.1 million, tax benefit of $0.4 million and tax expense of $0.2 million, respectively	2.5	(8.4)	16.4
Less: Reclassification adjustments included in net earnings	0.0	(0.4)	0.0
Foreign currency translation adjustments	2.5	(8.8)	16.4
Unrealized gains (losses) on investment, net of tax expense of $0.0 million, $0.0 million and $30.2 million, respectively	0.0	0.0	56.2
Pension liability adjustments, net of tax benefit of $0.3 million, tax expense of $0.2 million and tax benefit of $0.1 million, respectively	(1.3)	0.8	(0.6)
Less: Reclassification adjustments included in net earnings	0.1	0.1	0.1
Pension liability adjustments	(1.2)	0.9	(0.5)
Other comprehensive income (loss)	1.3	(7.9)	72.1
Comprehensive income	$ 113.7	$ 15.0	$ 143.7