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Debt (Narrative) (Details) - USD ($) $ in Millions	Mar. 31, 2016	Dec. 31, 2015
Senior Notes [Member] \| 4.875% Senior Notes [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate (percentage)	4.875%
Other Accrued Expenses [Member]
Debt Instrument [Line Items]
Debt instrument, accrued interest payable	$ 3.4	$ 7.7
Accounting Standards Update 2015-03 [Member] \| Debt [Member]
Debt Instrument [Line Items]
Adoption of new accounting pronouncement, reclassification of deferred financing costs from other assets to debt		(12.9)
Accounting Standards Update 2015-03 [Member] \| Debt [Member] \| Senior Notes [Member] \| 4.875% Senior Notes [Member]
Debt Instrument [Line Items]
Adoption of new accounting pronouncement, reclassification of deferred financing costs from other assets to debt		(6.4)
Accounting Standards Update 2015-03 [Member] \| Debt [Member] \| Revolving Credit Facility [Member] \| Credit Facility [Member]
Debt Instrument [Line Items]
Adoption of new accounting pronouncement, reclassification of deferred financing costs from other assets to debt		(5.5)
Accounting Standards Update 2015-03 [Member] \| Debt [Member] \| Term Loan [Member] \| Credit Facility [Member]
Debt Instrument [Line Items]
Adoption of new accounting pronouncement, reclassification of deferred financing costs from other assets to debt		$ (1.0)