Document and Entity Information - shares	6 Months Ended
	Jun. 30, 2017	Jul. 31, 2017
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Jun. 30, 2017
Document Fiscal Year Focus	2017
Document Fiscal Period Focus	Q2
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
Class A Common Stock
Entity Common Stock, Shares Outstanding		22,007,536
Class B Common Stock
Entity Common Stock, Shares Outstanding		17,948,131