Stock Transactions and Unit Redemptions - Additional Information (Details)			3 Months Ended				12 Months Ended
	Dec. 19, 2019 $ / shares shares	Oct. 30, 2019 $ / shares shares	Dec. 31, 2019 USD ($) vote class $ / shares shares	Sep. 30, 2019 $ / shares shares	Jun. 30, 2019 $ / shares shares	Mar. 31, 2019 $ / shares shares	Dec. 31, 2019 USD ($) shares vote class $ / shares	Dec. 31, 2018 USD ($) $ / shares shares	Aug. 01, 2018 USD ($)	Mar. 12, 2018 USD ($)	Dec. 31, 2017 shares
Class of Stock [Line Items]
Number of authorized classes of common stock | class			2				2
Class A Common Stock
Class of Stock [Line Items]
Common stock, votes per share | vote			1				1
Common stock, shares authorized (in shares)			1,000,000,000.0				1,000,000,000.0	1,000,000,000
Common stock, par value (in usd per share) | $ / shares			$ 0.01				$ 0.01	$ 0.01
Common stock, shares outstanding (in shares)			156,265,461				156,265,461	156,916,336			138,593,787
Shares repurchased (in shares)			4,568,002				4,568,002	50,000
Treasury stock repurchases (in shares)			625,597	2,279,373	1,613,032	0	4,518,002	50,000
Shares repurchased price (in dollars per share) | $ / shares			$ 12.97	$ 8.81	$ 8.61	$ 0	$ 9.32	$ 9.73
Share repurchase and redemption unit remaining authorized amount | $			$ 157,413,000				$ 157,413,000	$ 199,514,000
Class A Common Stock | Mr. Merkel
Class of Stock [Line Items]
Treasury stock repurchases (in shares)	132,429	55,193
Shares repurchased price (in dollars per share) | $ / shares	$ 13.61	$ 10.69
Class A Common Stock | Limited Partnership Interests or Other Equity Interests in Subsidiaries | Affiliated Persons or Entities
Class of Stock [Line Items]
Stock repurchases and redeemed or repurchases authorized amount | $										$ 100,000,000
Class A Common Stock | Maximum | Limited Partnership Interests or Other Equity Interests in Subsidiaries | Affiliated Persons or Entities
Class of Stock [Line Items]
Stock repurchases and redeemed or repurchases authorized amount | $									$ 200,000,000
Class B Common Stock
Class of Stock [Line Items]
Common stock, votes per share | vote			10				10
Common stock, shares authorized (in shares)			500,000,000				500,000,000	500,000,000
Common stock, par value (in usd per share) | $ / shares			$ 0.01				$ 0.01	$ 0.01
Conversion of common stock (in shares)							1
Common stock, shares outstanding (in shares)			21,285,533				21,285,533	21,285,533