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Organization and Business Operations - Financing - Additional Information (Details) - USD ($)			9 Months Ended
	Oct. 18, 2018	Jan. 19, 2017	Sep. 30, 2018	Sep. 30, 2017
Stockholders' Equity
Amount placed in trust account		$ 400,000,000		$ 400,000,000
Maximum maturity period (in days)			180 days
Redemption percentage for release of Trust Account funds			100.00%
Redemption percentage if business combination is not completed			100.00%
Proceeds from trust account to partially fund business combination			$ 406,591,570
Greenlight \| Subsequent Event
Stockholders' Equity
Aggregate consideration of business combination	$ 2,300,000,000
Combined proceeds from trust account and private placement	803,000,000
Rollover indebtedness	852,000,000
Stock consideration	$ 664,000,000
Maximum
Stockholders' Equity
Number of months to complete Business Combination			24 months