Equity-Based Compensation (Cash Paid to Settle Liability Awards) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
MSPP
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock units credited	$ 6,058	$ 3,137	$ 1,901
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted stock units credited	$ 84,299	$ 198,155	$ 94,047
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding, Number	389,189,000	646,669,000	519,668,000
Restricted stock units balance, vested and unvested	441,816	536,164
Management
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
MSPP expense, in thousands	$ 2,432	$ 8,565	$ 2,767

Management Stock Purchase Plan, Compensation Expense

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

+ References

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- Definition

Amount of cash paid related to share-based compensation liabilities.

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Number of equity instruments other than options outstanding, including both vested and non-vested instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(i)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(ii)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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