Document And Entity Information	3 Months Ended
	Mar. 31, 2021 shares
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Mar. 31, 2021
Document Transition Report	false
Entity File Number	001-14157
Entity Registrant Name	TELEPHONE AND DATA SYSTEMS, INC.
Entity Central Index Key	0001051512
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q1
Amendment Flag	false
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	36-2669023
Entity Address, Address Line One	30 North LaSalle Street, Suite 4000
Entity Address, City or Town	Chicago
Entity Address, State or Province	IL
Entity Address, Postal Zip Code	60602
City Area Code	(312)
Local Phone Number	630-1900
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Smaller Reporting Company	false
Emerging Growth Company	false
Entity Shell Company	false
Common Shares
Title of 12(b) Security	Common Shares, $.01 par value
Trading Symbol	TDS
Security Exchange Name	NYSE
Entity Common Stock, Shares Outstanding	107,093,000
Depository Shares each representing a 1/1000th interest in a share of 6.625% Series UU Cumulative Redeemable Perpetual Preferred Stock, $.01 par value
Title of 12(b) Security	Depository Shares each representing a 1/1000th interest in a share of 6.625% Series UU Cumulative Redeemable Perpetual Preferred Stock, $.01 par value
Trading Symbol	TDSPrU
Security Exchange Name	NYSE
6.625% Senior Notes
Title of 12(b) Security	6.625% Senior Notes due 2045
Trading Symbol	TDI
Security Exchange Name	NYSE
6.875% Senior Notes
Title of 12(b) Security	6.875% Senior Notes due 2059
Trading Symbol	TDE
Security Exchange Name	NYSE
7.0% Senior Notes
Title of 12(b) Security	7.000% Senior Notes due 2060
Trading Symbol	TDJ
Security Exchange Name	NYSE
5.875% Senior Notes
Title of 12(b) Security	5.875% Senior Notes due 2061
Trading Symbol	TDA
Security Exchange Name	NYSE
Series A Common Shares
Entity Common Stock, Shares Outstanding	7,293,000