Income Taxes - Income taxes relating to continuing operations and deferred taxes (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Current:
Federal	$ (47.2)	$ 61.8	$ 51.2
State and local	4.7	11.5	7.9
Foreign	41.0	40.1	43.5
Total current	(1.5)	113.4	102.6
Deferred:
Federal	140.6	40.1	42.9
State and local	22.3	8.4	9.3
Foreign	(0.7)	(3.9)	(1.7)
Total deferred	162.2	44.6	50.5
Income taxes relating to continuing operations	$ 160.7	$ 158.0	$ 153.1
Reconciliation of income taxes from continuing operations at federal statutory rate
Federal statutory income tax rate (as a percent)	35.00%	35.00%	35.00%
Income taxes relating to continuing operations at federal statutory rate of 35%	$ 177.8	$ 172.2	$ 160.3
State and local income taxes, net of federal taxes	14.7	13.3	11.0
Non-U.S. income taxed at other rates	(26.8)	(27.4)	(17.7)
Other	(5.0)	(0.1)	(0.5)
Income taxes relating to continuing operations	160.7	158.0	153.1
Deferred Tax Assets
Accrued liabilities	71.4	67.5
Net operating loss carryforwards	32.4	17.9
Other	18.7	26.2
Total deferred tax assets	122.5	111.6
Valuation allowance	(17.2)	(17.3)
Net deferred tax assets	105.3	94.3
Deferred Tax Liabilities
Depreciation and amortization	(210.9)	(198.1)
Partnership investments	(448.1)	(285.5)
Convertible notes	(5.0)	(7.5)
Other	(5.9)	(6.1)
Total deferred tax liabilities	(669.9)	(497.2)
Net deferred tax liabilities	(564.6)	(402.9)
Income from continuing operations before income taxes of non-U.S. subsidiaries	191.4	$ 182.5	$ 170.6
Amount of total temporary difference related to the excess of financial reporting basis over tax basis in the non-U.S. subsidiaries on which U.S. federal income taxes are not provided	$ 816.5