Shareholders' Equity - Schedule of Common Stock Outstanding (Details) - $ / shares	Sep. 30, 2019	Jun. 30, 2019	Dec. 31, 2018
Class of Stock [Line Items]
Common stock, shares outstanding (shares)	53,872,645		995
Common Class A
Class of Stock [Line Items]
Common stock, shares outstanding (shares)	47,361,352
Common Class C
Class of Stock [Line Items]
Common stock, shares outstanding (shares)	6,511,293
Shares outstanding not subject to an earn-out agreement
Class of Stock [Line Items]
Common stock, shares outstanding (shares)	47,024,809		995
Shares outstanding not subject to an earn-out agreement | Common Class A
Class of Stock [Line Items]
Common stock, shares outstanding (shares)	41,244,899
Shares outstanding not subject to an earn-out agreement | Common Class C
Class of Stock [Line Items]
Common stock, shares outstanding (shares)	5,779,910
Shares subject to a $15.00 earn-out
Class of Stock [Line Items]
Common stock, shares outstanding (shares)	2,940,336		0
Business combination, earn out price (usd per share)	$ 15.00		$ 15.00
Shares subject to a $15.00 earn-out | Common Class A
Class of Stock [Line Items]
Common stock, shares outstanding (shares)	2,940,336
Business combination, earn out price (usd per share)		$ 15.00
Shares subject to a $15.00 earn-out | Common Class C
Class of Stock [Line Items]
Common stock, shares outstanding (shares)	0
Shares subject to a $12.50 earn-out
Class of Stock [Line Items]
Common stock, shares outstanding (shares)	3,750,000		0
Business combination, earn out price (usd per share)	$ 12.50		$ 12.50
Shares subject to a $12.50 earn-out | Common Class A
Class of Stock [Line Items]
Common stock, shares outstanding (shares)	3,018,617
Business combination, earn out price (usd per share)		12.50
Shares subject to a $12.50 earn-out | Common Class C
Class of Stock [Line Items]
Common stock, shares outstanding (shares)	731,383
Shares subject to a $12.25 earn-out
Class of Stock [Line Items]
Common stock, shares outstanding (shares)	157,500		0
Business combination, earn out price (usd per share)	$ 12.25		$ 12.25
Shares subject to a $12.25 earn-out | Common Class A
Class of Stock [Line Items]
Common stock, shares outstanding (shares)	157,500
Business combination, earn out price (usd per share)		$ 12.25
Shares subject to a $12.25 earn-out | Common Class C
Class of Stock [Line Items]
Common stock, shares outstanding (shares)	0