Acquisition (as Restated) (Details) - Obalon Therapeutics Inc. - USD ($) $ in Millions		12 Months Ended
Jun. 15, 2021	Dec. 31, 2021
Acquisitions
Aggregate purchase price	$ 30.6
Issuance of shares of common stock	66,801
Shares issued value	$ 30.6
Cancellation of shares	53,607
General and administrative expense
Acquisitions
Acquisition related costs		$ 2.3

Number of shares of equity interests issued or issuable to acquire entity.

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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Amount of equity interests of the acquirer, including instruments or interests issued or issuable in consideration for the business combination.

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Number of stock bought back by the entity at the exercise price or redemption price.

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