Number of diluted Class A Common Shares Outstanding If Holding Partnership Units exchanged.

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

The cash outflow to reacquire common stock during the period.

+ References

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- Definition

Amount of stock repurchase plan authorized.

+ References

No definition available.

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- Definition

Amount remaining of a stock repurchase plan authorized.

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No definition available.

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- Definition

Total cost of shares repurchased divided by the total number of shares repurchased.

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- Definition

Number of shares that have been repurchased during the period and are being held in treasury.

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Net Income Per Share of Class A Common Stock - Additional Information (Details) - USD ($)	3 Months Ended	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2019	Jun. 30, 2018	Apr. 24, 2019
Earnings Per Share Basic [Line Items]
Class A common shares outstanding if all Holding Partnership Units exchanged	40,523,710	40,130,115
Treasury stock, shares		639,204
Treasury stock, average price per share		$ 40.15
Aggregate amount of shares repurchased		$ 25,684,000	$ 25,727,000
Class A Common Stock
Earnings Per Share Basic [Line Items]
Available amount remaining for repurchases	$ 107,200,000	$ 107,200,000
Class A Common Stock \| Maximum
Earnings Per Share Basic [Line Items]
Share repurchase program, authorized amount				$ 100,000,000