Equity - Accumulated Other Comprehensive Income (Details) $ in Millions	6 Months Ended
Jun. 30, 2016 USD ($)
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Balance beginning of period	$ 2,865.1
Unrealized (loss) gains, arising during the period	(156.5)
Noncontrolling interest	138.3
Amounts reclassified out of AOCI during the period, gross	4.5
Amounts reclassified out of AOCI during the period, tax	(1.8)
Taxes on unrealized gains (losses), arising during the period	6.6
Balance end of period	2,564.1
Foreign Currency Translation
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Balance beginning of period	(69.9)
Balance end of period	(75.8)
Currency Derivative Contracts
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Balance beginning of period	22.4
Balance end of period	19.3
Marketable Securities
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Balance beginning of period	(0.2)
Balance end of period	(0.1)
Accumulated Foreign Currency Adjustment Including Portion Attributable to Noncontrolling Interest [Member]
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Unrealized (loss) gains, arising during the period	(65.6)
Noncontrolling interest	51.6
Amounts reclassified out of AOCI during the period, gross	5.2
Amounts reclassified out of AOCI during the period, tax	(2.1)
Taxes on unrealized gains (losses), arising during the period	5.0
Accumulated Net Gain (Loss) from Cash Flow Hedges Including Portion Attributable to Noncontrolling Interest [Member]
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Unrealized (loss) gains, arising during the period	(91.1)
Noncontrolling interest	86.7
Amounts reclassified out of AOCI during the period, gross	(0.7)
Amounts reclassified out of AOCI during the period, tax	0.3
Taxes on unrealized gains (losses), arising during the period	1.7
Accumulated Net Investment Gain (Loss) Including Portion Attributable to Noncontrolling Interest [Member]
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Unrealized (loss) gains, arising during the period	0.2
Noncontrolling interest	0.0
Amounts reclassified out of AOCI during the period, gross	0.0
Amounts reclassified out of AOCI during the period, tax	0.0
Taxes on unrealized gains (losses), arising during the period	(0.1)
Total Accumulated Other Comprehensive Income
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Balance beginning of period	(47.7)
Balance end of period	$ (56.6)

Amount before tax and reclassification adjustments of other comprehensive income (loss).

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 14A
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