Related-Party Transactions - Additional Information (Detail)	9 Months Ended
	Sep. 30, 2018 USD ($) shares
Related Party Transaction [Line Items]
Aggregate amount of common stock may be sold | $	$ 5,000,000
Class A Common Stock [Member] | Exchange of Redeemable Non controlling Interest To Class A Common Stock [Member]
Related Party Transaction [Line Items]
Stock conversion ratio	1.00
MacAndrews & Forbes Incorporated [Member]
Related Party Transaction [Line Items]
Ownership percentage of majority owner	81.70%
Amount of cash savings percentage	85.00%
Description of tax receivable agreement	The Company and MacAndrews are party to a tax receivable agreement (the “Tax Receivable Agreement”), which provides for the payment by the Company to M&F TTP Holdings Two LLC (“M&F”), as successor in interest to vTv Therapeutics Holdings, LLC (“vTv Therapeutics Holdings”), and M&F TTP Holdings LLC (or certain of its transferees or other assignees) of 85% of the amount of cash savings, if any, in U.S. federal, state and local income tax or franchise tax that the Company actually realizes (or, in some circumstances, the Company is deemed to realize) as a result of (a) the exchange of Class B Common Stock, together with the corresponding number of vTv Units, for shares of the Company’s Class A Common Stock (or for cash), (b) tax benefits related to imputed interest deemed to be paid by the Company as a result of the Tax Receivable Agreement and (c) certain tax benefits attributable to payments under the Tax Receivable Agreement.
MacAndrews & Forbes Incorporated [Member] | Class B Common Stock [Member]
Related Party Transaction [Line Items]
Shares held by related party | shares	23,084,267
MacAndrews & Forbes Incorporated [Member] | Class A Common Stock [Member]
Related Party Transaction [Line Items]
Shares held by related party | shares	8,658,169
Aggregate amount of common stock may be sold | $	$ 10,000,000
MacAndrews & Forbes Incorporated [Member] | Class A Common Stock [Member] | Exchange of Redeemable Non controlling Interest To Class A Common Stock [Member]
Related Party Transaction [Line Items]
Stock conversion ratio	1.00