Stockholders' Equity (Details) $ / shares in Units, $ in Thousands	3 Months Ended	12 Months Ended
	Dec. 31, 2017 USD ($)	Dec. 31, 2019 USD ($) vote $ / shares shares	Dec. 31, 2018 USD ($) $ / shares shares	Dec. 31, 2017 USD ($) $ / shares	Oct. 10, 2017 $ / shares
Class of Stock [Line Items]
Common stock, par value (in dollars per share) | $ / shares					$ 0.001
Preferred stock, shares authorized (in shares) | shares		10,000,000	10,000,000
Preferred stock, par value (in dollars per share) | $ / shares		$ 0.001	$ 0.001
Dividends declared | $	$ 503	$ 9,414	$ 2,961
Retained Earnings
Class of Stock [Line Items]
Dividends declared | $	$ 503	$ 9,414	$ 2,961	$ 500
Class A
Class of Stock [Line Items]
Common stock, shares authorized (in shares) | shares		750,000,000	750,000,000
Common stock, par value (in dollars per share) | $ / shares		$ 0.001	$ 0.001
Votes per share | vote		1
Dividends paid (in dollars per share) | $ / shares		$ 0.1176	$ 0.059	$ 0.014
Class B
Class of Stock [Line Items]
Common stock, shares authorized (in shares) | shares		300,000,000	300,000,000
Common stock, par value (in dollars per share) | $ / shares		$ 0.001	$ 0.001
Treasury Stock, Shares, Retired | shares		65,600,000
Votes per share | vote		1
Class C
Class of Stock [Line Items]
Common stock, shares authorized (in shares) | shares		75,000,000	75,000,000
Common stock, par value (in dollars per share) | $ / shares		$ 0.001	$ 0.001
Treasury Stock, Shares, Retired | shares		42,900,000
Votes per share | vote		10