Income Taxes - Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Deferred tax assets:
Accounts receivable	$ 2.9	$ 2.0
Accrued expenses	4.6	4.7
Compensation	30.6	30.1
Investments		1.4
Deferred revenue	2.0	0.2
Net operating loss carryforwards	14.1	16.0
Fixed assets	0.8	0.8
Inventory	3.2	2.9
Foreign tax and other tax credit carryforwards	17.2	32.3
Unrealized currency gain/loss	3.0	6.1
Other		7.5
Gross deferred tax assets	78.4	104.0
Less valuation allowance	(0.5)	(37.2)	$ (57.4)	$ (42.4)
Total deferred tax assets	77.9	66.8
Deferred tax liabilities:
Accounts receivable		0.6
Foreign statutory reserves	1.1	5.3
Intangibles	7.2	9.4
Accrued expenses	1.2	8.0
Other	2.0
Total deferred tax liabilities	11.5	23.3
Net deferred tax assets	$ 66.4	$ 43.5