Document and Entity Information - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Feb. 14, 2017	Dec. 30, 2016
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2016
Document Fiscal Year Focus	2016
Document Fiscal Period Focus	FY
Trading Symbol	APTI
Entity Registrant Name	Apptio Inc
Entity Central Index Key	0001419625
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Well-known Seasoned Issuer	No
Entity Public Float			$ 434.2
Class A Common Stock
Entity Common Stock, Shares Outstanding		6,900,000
Class B Common Stock
Entity Common Stock, Shares Outstanding		31,484,315