Schedule of Accumulated Other Comprehensive Income (Loss) (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2013
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at beginning of period	$ 0.0	$ 0.2
Unrealized gains		0.2
Amounts realized in earnings		(0.4)
Currency translation adjustments	(6.0)
Pension benefit adjustments	7.1
Deferred tax expense on pension benefit adjustments	(2.1)
Balance at end of period	(1.0)	0.0
Unrealized Gains on Investment Securities, Available for Sale
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at beginning of period	0.0	0.2
Unrealized gains		0.2
Amounts realized in earnings		(0.4)
Balance at end of period		0.0
Currency Translation
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at beginning of period	0.0
Currency translation adjustments	(6.0)
Balance at end of period	(6.0)	0.0
Pension Benefit Adjustment
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at beginning of period	0.0
Pension benefit adjustments	7.1
Deferred tax expense on pension benefit adjustments	(2.1)
Balance at end of period	$ 5.0	$ 0.0