Assets Held for Sale Asset Held For Sale (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Long Lived Assets Held-for-sale [Line Items]
Portfolio Proceeds			$ 99.1	$ 123.8
Disposition Gains on Owned Assets	$ 12.7	$ 5.1	33.8	25.1
Asset Impairment Charges	1.9	1.8	1.9	1.8
Assets Held-for-sale, Long Lived, Fair Value Disclosure	21.3		21.3		$ 89.5
Portfolio Management [Member]
Long Lived Assets Held-for-sale [Line Items]
Disposition Gains on Owned Assets	1.8	2.1	1.8	4.5
Asset Impairment Charges	0.0	1.8	0.0	1.8
Assets Held-for-sale, Long Lived, Fair Value Disclosure	19.2		19.2		45.6
Rail North America [Member]
Long Lived Assets Held-for-sale [Line Items]
Disposition Gains on Owned Assets	10.9	3.0	32.0	20.6
Asset Impairment Charges	1.9	$ 0.0	1.9	$ 0.0
Assets Held-for-sale, Long Lived, Fair Value Disclosure	$ 2.1		$ 2.1		$ 43.9
Marine vessels [Member] | Portfolio Management [Member]
Long Lived Assets Held-for-sale [Line Items]
Property, Plant and Equipment, Dispositions			26.4
Portfolio Proceeds			$ 28.2
Railcars [Member] | Rail North America [Member]
Long Lived Assets Held-for-sale [Line Items]
Property, Plant and Equipment, Dispositions			21.8
Portfolio Proceeds			$ 49.9
Property, Plant and Equipment, Transfers and Changes			19.7
Railcars [Member]
Long Lived Assets Held-for-sale [Line Items]
Disposition Gains on Owned Assets			$ 28.1