Stock-Based Compensation Plans (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Financial Designation, Predecessor and Successor [Fixed List]		Predecessor		Predecessor
Equity-settled PRSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense	$ 7,136		$ 18,807
Compensation expense, net of taxes	$ 7,136		$ 18,807
Weighted-average grant date fair value per unit, PRSUs	$ 21.65		$ 21.65
Cash-settled PRSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Financial Designation, Predecessor and Successor [Fixed List]		Predecessor		Predecessor
Compensation expense	$ 219	$ 4,794	$ 738	$ 15,949
Compensation expense, net of taxes	$ 219	$ 4,794	$ 738	$ 15,949
Weighted-average grant date fair value per unit, PRSUs	$ 54,150	$ 38,017	$ 54,150	$ 38,017
Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Financial Designation, Predecessor and Successor [Fixed List]		Predecessor		Predecessor
Compensation expense	$ 1,995		$ 22,398
Compensation expense, net of taxes	$ 1,995		$ 22,398
Weighted-average fair value per unit, options	$ 1.96		$ 1.96
Total fair value of vested options	$ 16,309		$ 16,309

Represents the total fair value of options vested during the reporting period.

No definition available.

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- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section S99
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-Publisher FASB
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-Section 50
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- Definition

Amount, after tax, of expense for award under share-based payment arrangement.

+ References

No definition available.

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- Definition

Indicates designation of financial information when substantially all business or separately identifiable line of business transfers from one entity to another entity. Acceptable values are "Predecessor" and "Successor".

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 852
-SubTopic 10
-Section 45
-Paragraph 27
-URI http://asc.fasb.org/extlink&oid=116635682&loc=SL2890601-112764

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- Definition

Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

+ 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
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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

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- Definition

Weighted average grant-date fair value of non-vested options outstanding.

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No definition available.

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