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Equity-Based Compensation (Performance Stock Units) (Details) - USD ($) $ in Thousands | 1 Months Ended | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | --- | ---
Jan. 31, 2016 | Sep. 30, 2016 | Sep. 30, 2016 | Sep. 30, 2015 | Dec. 31, 2013
Performance Stock Units - Settled in Cash [Member] |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Number of Awards (in shares) |  |  | 128,000 | 219,000 |
Restricted stock units credited |  |  | $ 3,100 | $ 4,039 |
Performance stock units |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Typical vesting period, in years |  |  | 3 years |  |
Performance period |  |  | 1 year |  |
Number of Awards (in shares) |  |  | 0 | 321,714 |
Percentage of target performance stock units earned |  |  | 200.00% |  |
PSUs earned |  |  | 438,000 |  |
Share-based liabilities paid (in $1000s) | $ 2,723 |  |  |  |
Closing price for number of days trailing |  | 90 days |  |  |
Performance stock units | Awarded January 2013 |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |
Percentage of target performance stock units earned |  |  | 50.00% |  |
Performance stock units earned |  |  | 114,000 |  |
Performance stock units target awards |  |  |  |  | 237,000

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- Definition Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + 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 (a)(1) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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