v3.21.1

Summary of Significant Accounting Policies - Summary of Basic and Diluted Net Income (Loss) Per Common Share (Detail)	3 Months Ended
	Mar. 31, 2021 USD ($) $ / shares shares
Numerator: Earnings allocable to common stock subject to possible redemption
Income from investments held in Trust Account	$ 11,969
Less: Company's portion available to be withdrawn to pay taxes	(11,969)
Net income attributable to Class A common stock subject to possible redemption
Numerator: Net Loss minus Net Earnings
Net loss	(3,365,259)
Net income allocable to Class A common stock subject to possible redemption
Non-redeemable net loss	$ (3,365,259)
Redeemable Common Stock [Member]
Denominator: Weighted average common stock
Basic and diluted weighted average shares outstanding \| shares	20,775,727
Basic and diluted net income/(loss) per share \| $ / shares	$ 0.00
Non Redeemable Common Stock [Member]
Denominator: Weighted average common stock
Basic and diluted weighted average shares outstanding \| shares	6,075,038
Basic and diluted net income/(loss) per share \| $ / shares	$ (0.55)

Earnings allocable to common stock subject to possible redemption [Abstract].

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Taxes on investments held in trust account.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Kensington Capital Acquisition Corp. II 10-Q