Aggregate carrying amount of the estimated litigation liability for known or estimated probable loss from litigation, which may include attorneys' fees and other litigation costs.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=25496072&loc=d3e14326-108349

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section S99
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-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Amount of judgment or settlement awarded to (against) the entity in respect of litigation.

+ References

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Amount of loss contingency liability.

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- Definition

Amount charged against operating income increasing loss contingency liability, after adjustments to reduce previously estimated charges.

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- Definition

Reflects the estimated amount of loss from the specified contingency as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)
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- Definition

Amount of unrecognized tax benefits.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15A
-Subparagraph (a)
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Unrecognized Tax Benefit
-URI http://asc.fasb.org/extlink&oid=6527854

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Contingencies - Narrative (Details) £ in Millions, $ in Millions		1 Months Ended		3 Months Ended
	Jan. 18, 2017 USD ($)	Jan. 31, 2014 USD ($)	Jan. 31, 2014 GBP (£)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)
Loss Contingencies [Line Items]
Legal reserves				$ 90.0
Unrecognized tax benefits				71.0	$ 63.0	$ 163.0
GovEx Inquiry
Loss Contingencies [Line Items]
Litigation reserve				3.0
Legal Reserve \| Invoicing Matter
Loss Contingencies [Line Items]
Estimate of possible loss				340.0
Regulatory Matter \| Transition Management
Loss Contingencies [Line Items]
Legal reserves				65.0
Loss accruals				$ 23.0
U.K. FCA \| Regulatory Matter \| Transition Management
Loss Contingencies [Line Items]
Settlement, amount		$ (37.8)	£ (22.9)
Subsequent Event \| Department of Justice \| Regulatory Matter \| Transition Management
Loss Contingencies [Line Items]
Settlement, amount	$ (32.3)
Subsequent Event \| SEC \| Regulatory Matter \| Transition Management
Loss Contingencies [Line Items]
Settlement, amount	$ (32.3)