Document and Entity Information - shares	3 Months Ended
	Dec. 31, 2020	Feb. 02, 2021
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Dec. 31, 2020
Document Transition Report	false
Entity File Number	0-18059
Entity Registrant Name	PTC Inc.
Entity Incorporation, State or Country Code	MA
Entity Tax Identification Number	04-2866152
Entity Address, Address Line One	121 Seaport Boulevard
Entity Address, City or Town	Boston
Entity Address, State or Province	MA
Entity Address, Postal Zip Code	02210
City Area Code	781
Local Phone Number	370-5000
Title of 12(b) Security	Common Stock, $.01 par value per share
Trading Symbol	PTC
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		116,810,418
Amendment Flag	false
Entity Central Index Key	0000857005
Current Fiscal Year End Date	--09-30
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q1