Stock Issued During Period, Shares, Exchange of Securities

No definition available.

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Period Type:	duration

- Definition

Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

+ References

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-Publisher FASB
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+ Details

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Balance Type:	na
Period Type:	instant

- Definition

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

+ References

No definition available.

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- Definition

Number of equity instruments other than options outstanding, including both vested and non-vested instruments.

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-Publisher FASB
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- Definition

Number of shares used to settle grantee's tax withholding obligation for award under share-based payment arrangement.

+ References

No definition available.

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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of new stock issued during the period.

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- Definition

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

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Stockholders' Equity - Share Activity by Class of Stock - shares	Total	Class A Common Stock	Class B Common Stock	Class C Common Stock	Common Stock	Common Stock Holdings GP Units	Common Stock Class B Common Stock	Common Stock Class C Common Stock	Restricted Stock	Restricted Stock Class A Common Stock	Restricted Stock Class B Common Stock	Restricted Stock Class C Common Stock	Restricted Stock Units RSUs	Common Stock	Common Stock Class A Common Stock	Common Stock Class B Common Stock	Common Stock Class C Common Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Restricted stock units outstanding (in shares)													246,581
Beginning balance (in shares) at Dec. 31, 2018	76,942,872		8,645,249	14,226,435
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Holdings Common Unit Exchanges (in shares)					0	(1,330,432)	(791,885)	(538,547)
Shares issued (in shares)									959,000	959,000	0	0
Restricted share award net share settlement (in shares)	(82,729)	(82,729)	0	0
Employee/Partner Terminations (in shares)														(16,865)	(16,865)	0	0
Ending balance (in shares) at Sep. 30, 2019	77,802,278	56,261,026	7,853,364	13,687,888
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Restricted stock units outstanding (in shares)													297,891