Consolidated Statements of Stockholders' Equity (Parenthetical) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010
Consolidated Statements of Stockholders' Equity
Issuance of convertible preferred stock, issuance costs	$ 66	$ 89

Represents the amount of decrease resulting from direct costs associated with issuing stock of convertible preferred stock during the period.

No definition available.

Name:	mkto_StockIssuedIssuanceCostsOfConvertiblePreferredStock
Namespace Prefix:	mkto_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration