Cover - USD ($) $ in Billions	12 Months Ended
	Dec. 31, 2019	Feb. 06, 2020	Jun. 30, 2019
Cover page.
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2019
Document Transition Report	false
Entity File Number	001-36373
Entity Registrant Name	TRINET GROUP, INC
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	95-3359658
Entity Address, Address Line One	One Park Place,
Entity Address, Address Line Two	Suite 600
Entity Address, City or Town	Dublin,
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	94568
City Area Code	510
Local Phone Number	352-5000
Title of 12(b) Security	Common stock par value $0.000025 per share
Trading Symbol	TNET
Security Exchange Name	NYSE
Entity Well Known Seasoned Issuer	Yes
Entity Voluntary Filers	No
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 Public Float			$ 3.0
Entity Common Stock, Shares Outstanding (in shares)		68,750,437
Documents Incorporated by Reference	Portions of the Registrant’s Definitive Proxy Statement to be issued in connection with its Annual Meeting of Stockholders, scheduled to be held on June 4, 2020, are incorporated by reference into Part III of this Form 10-K.
Document Year Focus	2019
Document Period Focus	FY
Amendment Flag	false
Current Year End Date	--12-31
Entity Central Index Key	0000937098