Debt Instrument Conversion Circumstance, Number of Trading Days

No definition available.

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- Definition

Principal Amount Per Note Used in Conversion Rate

+ References

No definition available.

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- Definition

Ratio of Common Stock Closing Price to Debt Conversion Price, Percentage

+ References

No definition available.

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- Definition

Carrying amount of long-term convertible debt as of the balance sheet date, net of the amount due in the next twelve months or greater than the normal operating cycle, if longer. The debt is convertible into another form of financial instrument, typically the entity's common stock.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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- Definition

The carrying amount of the equity component of convertible debt which may be settled in cash upon conversion.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109500613&loc=SL6031897-161870

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- Definition

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

+ References

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-Publisher FASB
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-SubTopic 20
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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
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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.

+ Details

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- Definition

The cash inflow from a debt initially having maturity due after one year or beyond the operating cycle, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
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- Definition

The cash outflow from the repayment of a long-term debt instrument which can be exchanged for a specified amount of another security, typically the entity's common stock, at the option of the issuer or the holder.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 230
-SubTopic 10
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-Paragraph 15
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- Definition

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
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-Topic 230
-SubTopic 10
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Credit Facilities and Debt Credit and Debt Facilities - 1% Convertible Debentures due 2035 (Details) - USD ($)	3 Months Ended			9 Months Ended	12 Months Ended
	Sep. 30, 2019	Dec. 31, 2017	Dec. 31, 2014	Jun. 30, 2017	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2017	Nov. 01, 2017	Mar. 13, 2017	Dec. 07, 2015	Oct. 24, 2011
Debt Instrument [Line Items]
Long-term debt, face value	$ 2,137,000,000.0				$ 2,137,000,000.0	$ 2,437,000,000.0
Proceeds from long-term debt, net of issuance costs					0	0	$ 837,482,000
Convertible Debentures One Percent Due Twenty Thirty Five [Member]
Debt Instrument [Line Items]
Long-term debt, face value										$ 676,500,000
Proceeds from long-term debt, net of issuance costs						$ 663,800,000
Convertible Debt, Noncurrent										495,400,000
Debt Instrument, Convertible, Carrying Amount of Equity Component										$ 181,100,000
Debt Instrument, Convertible, Conversion Price										$ 27.22
Convertible Debentures One Percent Due Twenty Thirty Five [Member] \| Minimum
Debt Instrument [Line Items]
Ratio of Common Stock Closing Price to Debt Conversion Price, Percentage										130.00%
Debt Instrument Conversion Circumstance Number Of Trading Days						20 days
Convertible Debentures One Percent Due Twenty Thirty Five [Member] \| Maximum
Debt Instrument [Line Items]
Ratio of Common Stock Closing Price to Debt Conversion Price, Percentage										98.00%
Debt Instrument Conversion Circumstance Number Of Trading Days						30 days
Principal Amount Per Note Used In Conversion Rate										$ 1,000
2.75% Convertible Debentures due November 1, 2031
Debt Instrument [Line Items]
Long-term debt, face value								$ 46,600,000		$ 395,500,000	$ 690,000,000.0
Proceeds from long-term debt, net of issuance costs						$ 253,200,000
Repayments of Convertible Debt	256,200,000	$ 331,200,000	$ 38,300,000		17,800,000	38,300,000	$ 256,200,000
Convertible Debt, Noncurrent											533,600,000
Debt Instrument, Convertible, Carrying Amount of Equity Component											$ 156,400,000
Debt Instrument, Convertible, Conversion Price											$ 32.30
Principal Amount Per Note Used In Conversion Rate	$ 1,000				$ 1,000
2.75% Convertible Debentures due November 1, 2031 \| Minimum
Debt Instrument [Line Items]
Ratio of Common Stock Closing Price to Debt Conversion Price, Percentage	130.00%				130.00%
Debt Instrument Conversion Circumstance Number Of Trading Days					20 days
2.75% Convertible Debentures due November 1, 2031 \| Maximum
Debt Instrument [Line Items]
Ratio of Common Stock Closing Price to Debt Conversion Price, Percentage	98.00%				98.00%
Convertible Debentures 1.25% Due 2025 [Member]
Debt Instrument [Line Items]
Long-term debt, face value									$ 350,000,000.0
Proceeds from long-term debt, net of issuance costs				$ 343,600,000
Convertible Debt, Noncurrent									252,100,000
Debt Instrument, Convertible, Carrying Amount of Equity Component									$ 97,900,000
Debt Instrument, Convertible, Conversion Price									$ 22.22
Ratio of Common Stock Closing Price to Debt Conversion Price, Percentage	130.00%				130.00%
Convertible Debentures 1.25% Due 2025 [Member] \| Minimum
Debt Instrument [Line Items]
Debt Instrument Conversion Circumstance Number Of Trading Days					20 days
Term Loan Facility Due August Seventh Twenty Ninteen [Member]
Debt Instrument [Line Items]
Repayments of Debt						$ 472,500,000