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Employee Incentive Plans (2007 Stock Incentive Plan, ROI Summary) (Details) - 2007 Stock Incentive Plan (Shares)	3 Months Ended
	Mar. 31, 2019 shares	[1]
Beginning Balance	5,472,706
Shares Cancelled	(4,807)
Shares Distributed	(905)
Ending Balance	5,466,994
[1] Stock Incentive Plan number of granted restricted stock units related to 2018 was adjusted by 640 additional restricted stock units during the three months ended March 31, 2019.

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- Definition

Shares granted, net of shares distributed and forfeited.

+ References

No definition available.

+ Details

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- Definition

Total shares distributed during the period.

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No definition available.

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- Definition

Shares cancelled during the period.

+ References

No definition available.

+ Details

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Period Type:	duration

X

- Details

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Namespace Prefix:
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Period Type: