Stock-Based Compensation - PSUs to be Settled in Common Stock (Details) - USD ($) $ / shares in Units, $ in Thousands, shares in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Non-cash stock compensation expense	$ 52,013	$ 52,484	$ 46,448
PSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Required performance period	3 years
Performance units granted (in shares)	0.4	0.3	0.3
Weighted average grant date fair value (in dollars per share)	$ 15.49	$ 12.24	$ 17.63
Non-cash stock compensation expense	$ 6,500	$ 8,600	$ 5,400
Awards vested (in shares)	0.2	0.1	0.1
Number of common shares issued in connection with performance units (in shares)	0.4	0.1	0.1
PSUs \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance units performance percentage	0.00%
PSUs \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance units performance percentage	200.00%

Performance Based Award Performance Percentage

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- Definition

Amount of noncash expense for share-based payment arrangement.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
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- Definition

Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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-Publisher FASB
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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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Number of shares issued under share-based payment arrangement.

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