Condensed Consolidated Statements of Redeemable Convertible Preferred Stock and Stockholders' Equity (Parenthetical) $ in Thousands	3 Months Ended
Jun. 30, 2021 USD ($)
Statement of Stockholders' Equity [Abstract]
Net issuance costs of redeemable convertible preferred stock	$ 198

Net issuance costs of redeemable convertible preferred stock.

No definition available.

Name:	ampl_NetIssuanceCostsOfRedeemableConvertiblePreferredStock
Namespace Prefix:	ampl_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration