QUARTERLY FINANCIAL INFORMATION - Balance Sheet Data (Details) - USD ($)	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017
QUARTERLY FINANCIAL INFORMATION
Cash	$ 4,440,816	$ 4,573,852	$ 22,186
Marketable securities held in Trust Account	461,549,163	461,069,825
Total assets	466,268,939	465,909,927	290,314
Deferred underwriting fees	16,100,000	16,100,000
Total liabilities	16,286,126	16,459,008	267,000
Common stock subject to possible redemption	444,982,812	444,450,918
Total Stockholders' Equity	$ 5,000,001	$ 5,000,001	$ 23,314

Aggregate carrying value as of the balance sheet date of the deferred underwriting commission payable.

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Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Excludes cash and cash equivalents within disposal group and discontinued operation.

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Sum of the carrying amounts as of the balance sheet date of all liabilities that are recognized. Liabilities are probable future sacrifices of economic benefits arising from present obligations of an entity to transfer assets or provide services to other entities in the future.

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Total debt and equity financial instruments including: (1) securities held-to-maturity, (2) trading securities, and (3) securities available-for-sale which are intended to be held for greater than one year or the normal operating cycle, whichever is longer and that are pledged to one or more secured parties who have the right to buy, sell, or re-pledge the collateral.

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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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Carrying amount, attributable to parent, of an entity's issued and outstanding stock which is not included within permanent equity. Temporary equity is a security with redemption features that are outside the control of the issuer, is not classified as an asset or liability in conformity with GAAP, and is not mandatorily redeemable. Includes any type of security that is redeemable at a fixed or determinable price or on a fixed or determinable date or dates, is redeemable at the option of the holder, or has conditions for redemption which are not solely within the control of the issuer. Includes stock with a put option held by an ESOP and stock redeemable by a holder only in the event of a change in control of the issuer.

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