Units Outstanding (Details)	6 Months Ended
Jun. 30, 2019 shares
Units Outstanding
Outstanding as of December 31, 2018 (in units)	96,658,278
Options exercised (in units)	406,235
Units issued (in units)	2,068,514
Units retired (in units)	(2,508,578)
Outstanding as of June 30, 2019 (in units)	96,624,449

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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- Definition

Number of shares issued under share-based payment arrangement.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
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- Definition

Number of shares issued which are neither cancelled nor held in the treasury.

+ References

No definition available.

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- Definition

Total number of shares issued during the period, including shares forfeited, as a result of Restricted Stock Awards.

+ References

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-Publisher FASB
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-Topic 505
-SubTopic 10
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- Definition

Number of shares that have been repurchased and retired during the period.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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