Discontinued Operations (Schedule of Condensed Balance Sheet Aerospace Discontinued Operations) (Details) - USD ($) $ in Millions	Sep. 30, 2017	Dec. 31, 2016
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Assets of discontinued operations	$ 562.0	$ 13,220.7
Liabilities of discontinued operations	563.7	3,737.7
Discontinued Operations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Total cash and deposits	6.5	764.8
Net Loans	498.1	1,421.7
Operating lease equipment, net	19.6	9,677.6
Goodwill	0.0	126.8
Other assets	37.8	1,229.8
Assets of discontinued operations	562.0	13,220.7
Secured borrowings	293.6	1,571.0
Other liabilities	270.1	2,166.7
Liabilities of discontinued operations	563.7	3,737.7
Aerospace | Discontinued Operations
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Total cash and deposits	0.0	759.0
Net Loans	198.9	1,047.7
Operating lease equipment, net	19.6	9,677.6
Goodwill	0.0	126.8
Other assets	(3.2)	1,161.5
Assets of discontinued operations	215.3	12,772.6
Secured borrowings	0.0	1,204.6
Other liabilities	9.3	1,597.3
Liabilities of discontinued operations	$ 9.3	2,801.9
Deposits on commercial aerospace equipment		1,013.7
Maintenance reserves		1,084.9
Security deposits		$ 167.0