Debt Instrument, Repurchased Face Amount Net of Debt Issuance

No definition available.

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- Definition

Debt Instrument, Repurchased Face Amount Net of Exchanged Notes

+ References

No definition available.

+ Details

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- Definition

Face (Par) Amount of the Original Debt Instrument, Including Repurchases and Equity Exchanges

+ References

No definition available.

+ Details

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

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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

Face (par) amount of the original debt instrument that was repurchased.

+ References

No definition available.

+ Details

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- Definition

Amount of unamortized debt discount (premium) and debt issuance costs.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28555-108399

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- Definition

Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6802200&loc=d3e1835-112601

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 3
-Subparagraph (SX 210.12-04.(a))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24072-122690

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- Definition

Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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- Definition

Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 3
-Subparagraph (SX 210.12-04.(a))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24072-122690

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6802200&loc=d3e1835-112601

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- Definition

Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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(Aggregate Maturities Of Long-Term Debt) (Details) - USD ($) $ in Millions	Mar. 31, 2018	Feb. 28, 2018	Feb. 09, 2018	Dec. 31, 2017	Mar. 31, 2017	Dec. 31, 2016	Mar. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2011
Debt Instrument [Line Items]
Long-Term Debt, Gross				$ 4,882.8		$ 6,549.5
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net				132.1
Senior Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Repurchased Face Amount				(194.1)		(1,130.6)
Face (Par) Amount of the Original Debt Instrument, Including Repurchases and Equity Exchanges						(1,155.1)
Debt Instrument, Repurchased Face Amount Net of Exchanged Notes					$ (317.5)
Senior Notes [Member] \| 8.50% Senior notes due 2019
Debt Instrument [Line Items]
Debt Instrument, Repurchased Face Amount				(54.6)	(145.8)	(62.0)
Long-Term Debt, Maturities, Repayments of Principal in Year Three						500.0
Long-Term Debt, Maturities, Repayments of Principal in Year Four				237.6
Face (Par) Amount of the Original Debt Instrument, Including Repurchases and Equity Exchanges						(62.0)
Debt Instrument, Face Amount										$ 500.0
Senior Notes [Member] \| 6.875% Senior notes due 2020
Debt Instrument [Line Items]
Debt Instrument, Repurchased Face Amount				(100.1)	(129.8)	(219.2)
Long-Term Debt, Maturities, Repayments of Principal in Year Four						900.0
Long-Term Debt, Maturities, Repayments of Principal in Year Five				450.9
Face (Par) Amount of the Original Debt Instrument, Including Repurchases and Equity Exchanges						(219.2)
Debt Instrument, Face Amount										900.0
Senior Notes [Member] \| 4.70% Senior notes due 2021
Debt Instrument [Line Items]
Debt Instrument, Repurchased Face Amount				(39.4)	(373.9)	(817.0)
Long-Term Debt, Maturities, Repayments of Principal in Year Five						1,500.0
Long-Term Debt, Maturities, Repayments of Principal after Year Five				269.7
Face (Par) Amount of the Original Debt Instrument, Including Repurchases and Equity Exchanges						(817.0)
Debt Instrument, Face Amount										1,500.0
Senior Notes [Member] \| 4.50% Senior notes due 2024
Debt Instrument [Line Items]
Debt Instrument, Repurchased Face Amount						(1.7)
Long-Term Debt, Maturities, Repayments of Principal after Year Five				623.3		625.0
Face (Par) Amount of the Original Debt Instrument, Including Repurchases and Equity Exchanges						(1.7)
Debt Instrument, Face Amount									$ 625.0
Senior Notes [Member] \| 8.00% Senior notes due 2024
Debt Instrument [Line Items]
Long-Term Debt, Maturities, Repayments of Principal after Year Five				332.0		0.0
Debt Instrument, Face Amount				332.0	$ 332.0
Senior Notes [Member] \| 5.20% Senior notes due 2025
Debt Instrument [Line Items]
Debt Instrument, Repurchased Face Amount						(30.7)
Long-Term Debt, Maturities, Repayments of Principal after Year Five				669.3		700.0
Face (Par) Amount of the Original Debt Instrument, Including Repurchases and Equity Exchanges						(30.7)
Debt Instrument, Face Amount								$ 700.0
Senior Notes [Member] \| 7.20% Senior notes due 2027
Debt Instrument [Line Items]
Long-Term Debt, Maturities, Repayments of Principal after Year Five				150.0		150.0
Debt Instrument, Face Amount						150.0
Senior Notes [Member] \| 7.875% Senior notes due 2040
Debt Instrument [Line Items]
Long-Term Debt, Maturities, Repayments of Principal after Year Five				300.0		300.0
Debt Instrument, Face Amount										$ 300.0
Senior Notes [Member] \| 5.75% Senior notes due 2044
Debt Instrument [Line Items]
Debt Instrument, Repurchased Face Amount						(24.5)
Long-Term Debt, Maturities, Repayments of Principal after Year Five				1,000.5		1,025.0
Face (Par) Amount of the Original Debt Instrument, Including Repurchases and Equity Exchanges						(24.5)
Debt Instrument, Face Amount							$ 400.0		$ 625.0
Convertible Debt [Member] \| 3.00% Exchangeable senior notes due 2024
Debt Instrument [Line Items]
Long-Term Debt, Maturities, Repayments of Principal after Year Five				849.5		849.5
Debt Instrument, Face Amount				849.5		849.5
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net				$ (213.8)		$ (245.2)
Scenario, Forecast
Debt Instrument [Line Items]
Long-Term Debt, Gross	$ 5,232.4
Scenario, Forecast \| Senior Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Repurchased Face Amount	(650.4)
Debt Instrument, Repurchased Face Amount Net of Debt Issuance	349.6
Scenario, Forecast \| Senior Notes [Member] \| 8.50% Senior notes due 2019
Debt Instrument [Line Items]
Debt Instrument, Repurchased Face Amount	(237.6)	$ (55.0)	$ (182.6)
Long-Term Debt, Maturities, Repayments of Principal in Year Four	0.0
Scenario, Forecast \| Senior Notes [Member] \| 6.875% Senior notes due 2020
Debt Instrument [Line Items]
Debt Instrument, Repurchased Face Amount	(256.6)
Long-Term Debt, Maturities, Repayments of Principal in Year Five	194.3
Scenario, Forecast \| Senior Notes [Member] \| 4.70% Senior notes due 2021
Debt Instrument [Line Items]
Debt Instrument, Repurchased Face Amount	(156.2)
Long-Term Debt, Maturities, Repayments of Principal after Year Five	113.5
Scenario, Forecast \| Senior Notes [Member] \| 4.50% Senior notes due 2024
Debt Instrument [Line Items]
Long-Term Debt, Maturities, Repayments of Principal after Year Five	623.3
Scenario, Forecast \| Senior Notes [Member] \| 8.00% Senior notes due 2024
Debt Instrument [Line Items]
Long-Term Debt, Maturities, Repayments of Principal after Year Five	332.0
Scenario, Forecast \| Senior Notes [Member] \| 5.20% Senior notes due 2025
Debt Instrument [Line Items]
Long-Term Debt, Maturities, Repayments of Principal after Year Five	669.3
Scenario, Forecast \| Senior Notes [Member] \| 7.75% Senior notes due 2026
Debt Instrument [Line Items]
Long-Term Debt, Maturities, Repayments of Principal after Year Five	1,000.0
Debt Instrument, Face Amount	1,000.0
Scenario, Forecast \| Senior Notes [Member] \| 7.20% Senior notes due 2027
Debt Instrument [Line Items]
Long-Term Debt, Maturities, Repayments of Principal after Year Five	150.0
Scenario, Forecast \| Senior Notes [Member] \| 7.875% Senior notes due 2040
Debt Instrument [Line Items]
Long-Term Debt, Maturities, Repayments of Principal after Year Five	300.0
Scenario, Forecast \| Senior Notes [Member] \| 5.75% Senior notes due 2044
Debt Instrument [Line Items]
Long-Term Debt, Maturities, Repayments of Principal after Year Five	1,000.5
Scenario, Forecast \| Convertible Debt [Member] \| 3.00% Exchangeable senior notes due 2024
Debt Instrument [Line Items]
Long-Term Debt, Maturities, Repayments of Principal after Year Five	$ 849.5