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Employee Incentive Plans (2007 Stock Incentive Plan, ROI Summary) (Details) | 9 Months Ended
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Sep. 30, 2016 shares
2007 Stock Incentive Plan (Shares) |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Beginning Balance | 8,937,985 | [1]
Shares Forfeited | (66,137) |
Shares Distributed | (2,400,019) |
Ending Balance | 6,471,829 |
2007 ROI Unit Stock Plan (Shares) [Member] |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Beginning Balance | 6,370 |
Shares Distributed | (1,376) |
Ending Balance | 4,994 |
[1] | Stock Incentive Plan number of granted shares related to 2015 was adjusted by 12,454 additional shares during the nine months ended September 30, 2016.

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