Equity - Founder Shares (Details) - Founders Shares	9 Months Ended
	Jun. 30, 2018 $ / shares shares
Class of Stock [Line Items]
Shares issued (in shares) | shares	12,476,250
Percentage of shares subject to condition one	50.00%
Sale price equals or exceeds, condition one (USD per share)	$ 12.50
Number of trading days to meet condition one	20 days
Number of consecutive trading days to meet condition one	30 days
Percentage of shares subject to condition two	50.00%
Sale price equals or exceeds, condition two (USD per share)	$ 15.00
Number of trading days to meet condition two	20 days
Number of consecutive trading days to meet condition two	30 days