Adjustments To Additional Paid In Capital, Equity Component Of Convertible Debt, Tax Impact

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Capitalized Costs, Debt Issuance Costs

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Debt Instrument, Convertible, Period After Consecutive Trading Days

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Debt Instrument, Convertible, Ratio of Trading Price Per 1000 Principal Amount

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Amount of increase (decrease) in additional paid in capital (APIC) resulting from recognition of deferred taxes for convertible debt with a beneficial conversion feature.

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Adjustment to additional paid in capital resulting from the recognition of convertible debt instruments as two separate components - a debt component and an equity component. This bifurcation may result in a basis difference associated with the liability component that represents a temporary difference for purposes of applying accounting for income taxes. The initial recognition of deferred taxes for the tax effect of that temporary difference is as an adjustment to additional paid in capital.

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Exercise price per share or per unit of warrants or rights outstanding.

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Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.

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The price per share of the conversion feature embedded in the debt instrument.

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Ratio applied to the conversion of debt instrument into equity with equity shares divided by debt principal amount.

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Threshold period of specified consecutive trading days within which common stock price to conversion price of convertible debt instrument must exceed threshold percentage for specified number of trading days to trigger conversion feature.

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Minimum percentage of common stock price to conversion price of convertible debt instruments to determine eligibility of conversion.

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Threshold number of specified trading days that common stock price to conversion price of convertible debt instruments must exceed threshold percentage within a specified consecutive trading period to trigger conversion feature.

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Face (par) amount of debt instrument at time of issuance.

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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Contractual interest rate for funds borrowed, under the debt agreement.

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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.

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Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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The cash outflow for a financial contract that meets the hedge criteria as either cash flow hedge, fair value hedge or hedge of net investment in foreign operations.

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The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

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The cash inflow from issuance of rights to purchase common shares at predetermined price (usually issued together with corporate debt).

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Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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Long-Term Debt - 1.625% Notes due 2023 (Details) $ / shares in Units, shares in Millions, $ in Millions		12 Months Ended
	Mar. 31, 2017 USD ($) trading_day d $ / shares Rate shares	Dec. 31, 2019 USD ($) $ / shares	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Sep. 19, 2019 USD ($)	Jun. 12, 2019 USD ($)	May 31, 2018 USD ($)	Nov. 30, 2017 USD ($)
Debt Instrument [Line Items]
Debt issuance costs	$ 2.4	$ 34.0	$ 33.5		$ 17.5	$ 6.6	$ 1.1	$ 3.3
Conversion option recorded to equity				$ 113.1
Borrowings under debt agreements		1,404.8	15.3	1,106.2
Conversion option, debt discount				(55.7)
Payments for hedge		0.0	0.0	144.7
Proceeds from issuance of warrants		$ 0.0	$ 0.0	$ 85.2
Senior Revolving Credit Facility
Debt Instrument [Line Items]
Debt instrument, interest rate (as a percent)		3.30%	3.77%
Borrowings used to enter into convertible note hedge and warrant transactions	59.5
1.625% Notes
Debt Instrument [Line Items]
Debt instrument, interest rate (as a percent)		1.625%
Tax impact of coversion option and convertible note hedge and warrant transactions	11.0
1.625% Notes \| Convertible Debt
Debt Instrument [Line Items]
Principal amount of debt	$ 575.0
Debt instrument, interest rate (as a percent)	1.625%	1.625%	1.625%
Debt issuance costs	$ 13.7	$ 6.9	$ 8.5
Debt issuance costs capitalized	11.1
Conversion option recorded to equity	2.6
Borrowings under debt agreements	$ 562.1
Conversion rate \| Rate	4.82567%
Conversion price per share (in dollars per share) \| $ / shares	$ 20.72	$ 20.72
Redemption price percentage	100.00%
Conversion option, debt discount	$ 115.7
Effective interest rate (as a percent)	5.38%
Exercise price, warrants (in dollars per share) \| $ / shares	$ 30.70
Proceeds from issuance of warrants	$ 85.2
Debt Conversion One \| 1.625% Notes \| Convertible Debt
Debt Instrument [Line Items]
Threshold trading days \| trading_day	20
Threshold consecutive trading days \| trading_day	30
Threshold percentage of stock price trigger (greater than or equal to)	130.00%
Debt Conversion Two \| 1.625% Notes \| Convertible Debt
Debt Instrument [Line Items]
Threshold consecutive trading days \| d	5
Period immediately following consecutive trading days (in business days)	5 days
Ratio of trading price per 1000 principal amount (as a percent) (less than)	0.98
Embedded Derivative Financial Instruments \| 1.625% Notes \| Convertible Debt
Debt Instrument [Line Items]
Conversion price per share (in dollars per share) \| $ / shares	$ 20.72
Number of convertible shares \| shares	27.7
Payments for hedge	$ 144.7