Equity (Details) $ / shares in Units, $ in Millions	3 Months Ended	9 Months Ended
	Jun. 30, 2017 USD ($) $ / shares shares	Jun. 30, 2017 vote $ / shares shares	Sep. 30, 2016 shares
Class of Stock [Line Items]
Shares authorized (in shares)	300,000,000	300,000,000	300,000,000
Number of votes per common share (in vote) | vote		1
Shares issued (in shares)	89,281,617	89,281,617	89,286,936
Shares outstanding (in shares)	89,272,041	89,272,041	89,286,936
Warrants
Warrants (in shares)	50,025,000	50,025,000
Common stock to be purchased through warrants (in shares)	25,012,500	25,012,500
Strike price of warrants (USD per share) | $ / shares	$ 11.50	$ 11.50
Preferred Stock
Preferred shares authorized (in shares)	1,000,000	1,000,000	1,000,000
Preferred shares issued (in shares)	0	0	0
Preferred shares outstanding (in shares)	0	0	0
Treasury Stock
Treasury stock acquired (in shares)	9,576
Fair market value of treasury stock acquired | $	$ 0.1
Founders Shares
Class of Stock [Line Items]
Shares issued (in shares)	12,476,250	12,476,250
Percentage of shares subject to condition one	50.00%	50.00%
Sale price equals or exceeds, condition one (USD per share) | $ / shares	$ 12.50	$ 12.50
Number of trading days to meet condition one		20 days
Number of consecutive trading days		30 days
Percentage of shares subject to condition two	50.00%	50.00%
Sale price equals or exceeds, condition two (USD per share) | $ / shares	$ 15.00	$ 15.00