Merger Agreement - Additional Information (Detail) $ / shares in Units, $ in Millions		3 Months Ended
	Jun. 10, 2020 $ / shares shares	Mar. 31, 2021 USD ($) $ / shares	Mar. 31, 2020 USD ($)	Dec. 31, 2020 $ / shares	Jun. 10, 2020 € / shares
Business Acquisition [Line Items]
Common stock, par value		$ 0.0001		$ 0.0001
General and administrative expenses
Business Acquisition [Line Items]
Direct and indirect expense incurred related to merger and acquisitions \| $		$ 0.8	$ 0.7
JET, Merger Sub and Merger Sub II \| Merger Agreement
Business Acquisition [Line Items]
Merger agreement, description		On and subject to the terms and conditions set forth in the Merger Agreement, at the effective time of the Initial Merger, each issued and outstanding share of our common stock (other than any shares of our common stock owned by the Company, JET, Merger Sub I, Merger Sub II or any other direct or indirect wholly owned subsidiary of JET), will be converted into one share of common stock, par value $0.0001 per share, of the Initial Surviving Company (the “Initial Surviving Company Stock”). Each such share of Initial Surviving Company Stock will immediately thereafter be automatically exchanged for newly issued American depositary shares of JET (“JET ADS”) representing 0.6710 shares of the share capital of JET with a nominal value of €0.04 per share (“JET Shares”), with each JET ADS representing one-fifth of one JET Share (the “Merger Consideration”).
Common stock, par value	$ 0.0001
Number of American depositary shares exchanged for each common share \| shares	0.6710
Just Eat Takeaway Com N V \| Merger Agreement
Business Acquisition [Line Items]
Common stock, par value \| € / shares					€ 0.04

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