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- Definition

Fair value inputs offered quotes per fixed income investment.

+ References

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Amount of transfers of assets measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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The fair value of notes issued in noncash investing and financing activities.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

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Fair Value Measurements - Additional Information (Details) $ in Millions	3 Months Ended			12 Months Ended
	Dec. 31, 2016 USD ($) $ / Investment	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Dec. 31, 2017 USD ($) $ / Investment	Dec. 31, 2016 USD ($) $ / Investment
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Quotes per fixed income investment \| $ / Investment	2.1			2.0	2.1
Quotes per equity investment \| $ / Investment	3.9			4.0	3.9
Loan notes issued during the period					$ (130.0)
Silverton 2015
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loan notes issued during the period			$ (85.0)
Silverton 2016
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loan notes issued during the period		$ (125.0)
Silverton 2016, Third-party Funded [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loan notes issued during the period		(100.0)
Silverton 2017
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loan notes issued during the period	$ (130.0)			$ 0.0
Silverton 2017, Third-party Funded [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loan notes issued during the period		$ (105.0)		0.0
Recurring \| Level 3 \| Silverton
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Repayments of debt				(115.6)
Recurring \| Level 3 \| Silverton 2015
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Repayments of debt					(89.3)
Loan notes issued during the period					(105.0)
Recurring \| Level 3 \| Silverton 2016
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Repayments of debt				(115.6)
Loan notes issued during the period				$ 0.0
Non-U.S government
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Assets, Level 1 to Level 2 Transfers, Amount	$ 83.9				$ 83.9