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Equity-Based Compensation (Tables) | 3 Months Ended
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Mar. 31, 2018
Share-based Compensation [Abstract] |
Schedule Of Number Of Awards And Weighted Average Grant Date Fair Value | The following table provides the number of stock unit awards granted during the three months ended March 31, which will convert to shares upon vesting, along with the weighted average grant date fair values:
| 2018 |  | 2017
Awards | Number of Awards (1) |  | Weighted Average Grant Date Fair Value |  | Number of Awards (2) |  | Weighted Average Grant Date Fair Value
Performance stock units | 132,288 |  |  | $ | 33.35 |  |  | 98,482 |  |  | $ | 43.05 |
Restricted stock units | 67,055 |  |  | $ | 33.35 |  |  | 59,112 |  |  | $ | 43.05 |
Options | — |  |  | $ | — |  |  | 20,000 |  |  | $ | 43.05 |
Schedule of PSU Conversion | During the 2016 performance period, the participants earned an aggregate of 256,000 PSUs, representing 200% the targeted 2016 award of 128,000. This award will convert to cash payable in the first quarter of 2019.
Schedule Of Compensation Expense Recognized From Change In Fair Value And Vesting Of Performance Stock Units | The following table summarizes the compensation expense recognized for the PSUs, which will convert to cash, for the three months ended March 31, (in thousands):
| 2018 |  | 2017
PSUs compensation expense | $ | 706 |  |  | $ | 1,737 |
Management Stock Purchase Plan | The following table provides the number of restricted stock units credited to active participant accounts and the payments made with respect to restricted stock units issued under the MSPP during the three months ended March 31,
| 2018 |  | 2017
Restricted stock units credited | 63,937 |  |  | 98,770 |
Share-based liabilities paid (in thousands) | $ | 4,717 |  |  | $ | 2,353 |

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- Definition Tabular disclosure of employee stock purchase plan activity. + 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 (g) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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- Definition Tabular disclosure of the weighted-average grant-date fair value of equity options or other equity instruments granted during the year. + 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)(1) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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- Definition Tabular disclosure of the number and weighted-average grant date fair value for outstanding performance shares. + 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) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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