Debt - Narrative (Details)	3 Months Ended
Mar. 31, 2021 USD ($) $ / shares	Mar. 31, 2020 USD ($)
Debt Instrument [Line Items]
Total interest payments	$ 25,100,000	$ 13,000,000.0
9% Convertible Junior Subordinated Debentures
Debt Instrument [Line Items]
Conversion rate (in shares per $1,000 note)	0.0755932
Principal amount of notes used in determining conversion rate	$ 1,000
Convertible debt, conversion price (in dollars per share) \| $ / shares	$ 13.23
Stated interest rate	9.00%
Senior Notes \| 5.75% Senior Notes Due 2023
Debt Instrument [Line Items]
Stated interest rate	5.75%
Senior Notes \| 5.25% Senior Notes Due 2028
Debt Instrument [Line Items]
Stated interest rate	5.25%

The principal amount of notes used in the determination of the initial conversion rate, which is subject to adjustment.

No definition available.

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109500613&loc=SL6031898-161870

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
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- Definition

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

+ References

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-Topic 210
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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.

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- Definition

Amount of cash paid for interest, including, but not limited to, capitalized interest and payment to settle zero-coupon bond attributable to accreted interest of debt discount and debt instrument with insignificant coupon interest rate in relation to effective interest rate of borrowing attributable to accreted interest of debt discount; classified as operating and investing activities.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4297-108586

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