Stockholders' Equity (Narrative) (Details) $ / shares in Units, $ in Millions					1 Months Ended			3 Months Ended		9 Months Ended	12 Months Ended
	Dec. 27, 2022 USD ($) shares	Oct. 24, 2022 USD ($) shares	Nov. 06, 2020 USD ($)	Oct. 31, 2020 USD ($)	Oct. 31, 2024 USD ($)	Oct. 31, 2023 USD ($)	Dec. 31, 2022 USD ($) $ / shares shares	Dec. 31, 2022 USD ($) $ / shares shares	Dec. 31, 2021 USD ($) $ / shares shares	Sep. 30, 2022 USD ($)	Dec. 31, 2022 USD ($) period $ / shares shares	Dec. 31, 2021 USD ($) $ / shares shares	Dec. 31, 2020 USD ($) $ / shares	Dec. 31, 2019 USD ($)	Dec. 31, 2022 € / shares	Sep. 30, 2020 USD ($)
Class of Stock [Line Items]
Common stock, authorized (in shares) | shares							14,000,000,000	14,000,000,000	14,000,000,000		14,000,000,000	14,000,000,000
Preferred stock, authorized (in shares) | shares							10,000,000	10,000,000	10,000,000		10,000,000	10,000,000
Common stock, par value (in dollars per share) | $ / shares							$ 1.00	$ 1.00	$ 1		$ 1.00	$ 1
Preferred stock, par value (in dollars per share) | $ / shares							$ 1.00	$ 1.00	$ 1		$ 1.00	$ 1
Period post issuance date that preferred shares are optionally redeemable at liquidation price											5 years
Equity, Class of Treasury Stock [Line Items]
Repurchase of common stock (in shares) | shares											34,000,000	0
Amount repurchased | $												$ 662
Preferred stock, quarterly dividend declared | $								$ 36	$ 36
Common stock, quarterly dividend declared per common shares (in dollars per share) | $ / shares								$ 0.2775	$ 0.52		$ 1.11	$ 2.08	$ 2.08
Noncontrolling Interest [Line Items]
Redemption of nonconvertible cumulative preferred interests in subsidiary | $											$ 2,665	$ 0	$ 1,950
Discontinued Operations, Disposed of by Sale | Puerto Rico And U.S. Virgin Islands Operations
Noncontrolling Interest [Line Items]
Redemption of nonconvertible cumulative preferred interests in subsidiary | $			$ 1,950	$ 1,950
Tower Holdings
Noncontrolling Interest [Line Items]
Preferred interest issued | $														$ 6,000
Fixed future purchase option price | $														6,000
Distribution reset period											5 years
Period post issuance date that preferred interests can be called at issue price											5 years
Option to require redemption, certain contingent events, failure of subsidiary to pay preferred distributions, minimum number of periods | period											2
Telco LLC
Noncontrolling Interest [Line Items]
Preferred interest issued | $																$ 2,000
Initial preferred distribution percentage											4.25%
Distribution reset period											7 years
Period post issuance date that preferred interests can be called at issue price											7 years
Option to require redemption, certain contingent events, failure of subsidiary to pay preferred distributions, minimum number of periods | period											2
PR Holdings
Noncontrolling Interest [Line Items]
Preferred interest issued | $														$ 1,950
Initial preferred distribution percentage														4.75%
Stock Repurchase Program, March 2013
Equity, Class of Treasury Stock [Line Items]
Shares authorized for repurchase (in shares) | shares							300,000,000	300,000,000			300,000,000
Stock Repurchase Program, March 2014
Equity, Class of Treasury Stock [Line Items]
Shares authorized for repurchase (in shares) | shares							300,000,000	300,000,000			300,000,000
Amount outstanding (in shares) | shares							144,000,000	144,000,000			144,000,000
Preferred Stock – Series A
Class of Stock [Line Items]
Preferred stock, outstanding (in shares) | shares							48,000	48,000	48,000		48,000	48,000
Preferred stock, liquidation preference per share (in dollars/Euros per share) | $ / shares							$ 25,000	$ 25,000			$ 25,000
Preferred stock, dividend rate											5.00%
Noncontrolling Interest [Line Items]
Preferred stock, outstanding (in shares) | shares							48,000	48,000	48,000		48,000	48,000
Preferred Stock – Series A | Mobility II, LLC
Noncontrolling Interest [Line Items]
Preferred interest, securities issued (in shares) | shares											320,000,000
Preferred stock, dividend rate											7.00%
Put or redemption option, minimum exercise price calculation, value added to accrued and unpaid distributions (in dollars per share) | $ / shares											$ 25
Put or redemption option, minimum exercise price calculation, value added to accrued and unpaid distributions in the aggregate | $	$ 5,340						$ 5,340
Maximum shares of common stock required to deliver to settle put and redemption options (in shares) | shares											250,000,000
Noncontrolling Interest, Preferred Stock, Shares Of Common Stock Settled To Put And Redemption Options | shares		105,000,000
Redemption of nonconvertible cumulative preferred interests in subsidiary | $		$ 2,600
Noncontrolling Interest, Preferred Stock, Shares Outstanding | shares	213,000,000						213,000,000	213,000,000			213,000,000
Noncontrolling Interest, Preferred Stock, Shares Of Common Stock That Can Be Exercised To Put Or Redemption Options In Any 12 Month Period | shares											107,000,000
Noncontrolling Interest, Preferred Stock, Shares Of Common Stock That Can Be Exercised To Put Or Redemption Options In Any 12 Month Period, Value | $											$ 2,670
Preferred interest distributions | $											373
Preferred Stock – Series A | Mobility II, LLC | Accounts payable and accrued liabilities
Noncontrolling Interest [Line Items]
Redemption of nonconvertible cumulative preferred interests in subsidiary | $								$ 2,670
Preferred Stock – Series A | Mobility II, LLC | Other Noncurrent Liabilities
Noncontrolling Interest [Line Items]
Redemption of nonconvertible cumulative preferred interests in subsidiary | $								2,670
Preferred Stock – Series A | Forecast | Mobility II, LLC
Noncontrolling Interest [Line Items]
Redemption of nonconvertible cumulative preferred interests in subsidiary | $					$ 2,670	$ 2,670
Class A-1 | Tower Holdings
Noncontrolling Interest [Line Items]
Preferred interest issued | $										$ 1,500
Initial preferred distribution percentage										5.00%
Class A-2 | Tower Holdings
Noncontrolling Interest [Line Items]
Preferred interest issued | $							$ 4,500	$ 4,500			$ 4,500
Initial preferred distribution percentage											4.75%
Preferred Stock – Series B
Class of Stock [Line Items]
Preferred stock, outstanding (in shares) | shares							20,000	20,000	20,000		20,000	20,000
Preferred stock, liquidation preference per share (in dollars/Euros per share) | € / shares															€ 100,000
Preferred stock, dividend rate											2.875%
Noncontrolling Interest [Line Items]
Preferred stock, outstanding (in shares) | shares							20,000	20,000	20,000		20,000	20,000
Preferred Stock – Series C
Class of Stock [Line Items]
Preferred stock, outstanding (in shares) | shares							70,000	70,000	70,000		70,000	70,000
Preferred stock, liquidation preference per share (in dollars/Euros per share) | $ / shares							$ 25,000	$ 25,000			$ 25,000
Preferred stock, dividend rate											4.75%
Noncontrolling Interest [Line Items]
Preferred stock, outstanding (in shares) | shares							70,000	70,000	70,000		70,000	70,000