Unaudited Condensed Consolidated Statements of Changes in Shareholders' Equity - Parenthetical - $ / shares	Sep. 30, 2019	Jun. 30, 2019	Dec. 31, 2018
Shares subject to a $15.00 earn-out
Business combination, earn out price (usd per share)	$ 15.00		$ 15.00
Shares subject to a $15.00 earn-out | Common Class A
Business combination, earn out price (usd per share)		$ 15.00
Shares subject to a $12.50 earn-out
Business combination, earn out price (usd per share)	12.50		12.50
Shares subject to a $12.50 earn-out | Common Class A
Business combination, earn out price (usd per share)		12.50
Shares subject to a $12.25 earn-out
Business combination, earn out price (usd per share)	$ 12.25		$ 12.25
Shares subject to a $12.25 earn-out | Common Class A
Business combination, earn out price (usd per share)		$ 12.25