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Equity-Based Compensation (PSUs Eligible for Conversion to Cash) (Details) - Performance Shares - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Equity Based Compensation Percent Of Targeted Performance Stock Units Earned | 200.00% | 200.00% |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested, Number of Shares | 256,000 | 438,000 |  |
Percentage earned on target shares |  |  |  | 50.00%
Units earned based on target units |  |  |  | 237,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Units Earned and Convertible to Cash | 128,000 | 219,000 | 231,000 | 114,000
Aggregate fair value of vested share-based payment award | $ 3,100 | $ 4,039 | $ 4,233 |

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- Definition Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash. + 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 (d)(2) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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