Stockholders' and Mezzanine Equity (Preferred Interest Narrative) (Details) $ / shares in Units, $ in Millions			1 Months Ended	3 Months Ended	6 Months Ended	12 Months Ended
	Dec. 27, 2022 USD ($) shares	Oct. 24, 2022 USD ($) shares	Apr. 30, 2023 USD ($) shares	Mar. 31, 2025 USD ($)	Jun. 30, 2024 USD ($) shares	Dec. 31, 2028 USD ($)	Dec. 31, 2025 Rate	Dec. 31, 2024 USD ($) period $ / shares shares	Dec. 31, 2023 USD ($) shares	Dec. 31, 2022 USD ($)	Dec. 31, 2019 shares	Dec. 31, 2020 USD ($)	Sep. 30, 2020 USD ($)
Noncontrolling Interest [Line Items]
Redemption of nonconvertible cumulative preferred interests in subsidiary								$ 0	$ 5,333	$ 2,665
Preferred Stock – Series A
Noncontrolling Interest [Line Items]
Preferred stock, issued (in shares) | shares								48,000	48,000
Preferred stock, outstanding (in shares) | shares								48,000	48,000
Preferred Stock – Series B
Noncontrolling Interest [Line Items]
Preferred stock, issued (in shares) | shares								20,000	20,000
Preferred stock, outstanding (in shares) | shares								20,000	20,000
Mobility II, LLC | Preferred Stock – Series A
Noncontrolling Interest [Line Items]
Preferred interest, securities issued (in shares) | shares											320,000,000
Preferred stock, outstanding (in shares) | shares								0
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							$ 2,670
Noncontrolling Interest, Preferred Stock, Shares Outstanding | shares	213,000,000								213,000,000
Stock Redeemed or Called During Period, Shares | shares			213,000,000
Stock Redeemed or Called During Period, Value			$ 5,414
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
Mobility II, LLC | Preferred Stock – Series B
Noncontrolling Interest [Line Items]
Preferred interest, securities issued (in shares) | shares					2,000,000
Put or redemption option, minimum exercise price calculation, value added to accrued and unpaid distributions (in dollars per share) | $ / shares								$ 1,000
Initial preferred distribution percentage								6.80%
Redeemable Noncontrolling Interest, Equity, Preferred, Carrying Amount					$ 2,000
Tower Holdings
Noncontrolling Interest [Line Items]
Preferred interest issued												$ 6,000
Fixed future purchase option price								$ 6,000
Distribution reset period								5 years
Option to require redemption, certain contingent events, failure of subsidiary to pay preferred distributions, minimum number of periods | period								2
Tower Holdings | Class A-1
Noncontrolling Interest [Line Items]
Preferred interest issued								$ 1,500
Initial preferred distribution percentage								5.00%
Tower Holdings | Class A-2
Noncontrolling Interest [Line Items]
Preferred interest issued								$ 4,500
Initial preferred distribution percentage								4.75%
Tower Holdings | Tower Fixed Rate Interests
Noncontrolling Interest [Line Items]
Initial preferred distribution percentage								5.90%
Tower Holdings | Tower Fixed Rate Interests | Subsequent Event
Noncontrolling Interest [Line Items]
Secured Overnight Financing Rate, Basis Spread | Rate							2.50%
Tower Holdings | Tower Floating Rate Interests | Forecast
Noncontrolling Interest [Line Items]
Preferred interest distributions						$ 525
Telco LLC
Noncontrolling Interest [Line Items]
Period post issuance date that preferred interests can be called at issue price								7 years
Telco LLC | Preferred Stock – Series A
Noncontrolling Interest [Line Items]
Preferred interest issued								$ 7,250	$ 7,250
Option to require redemption, certain contingent events, failure of subsidiary to pay preferred distributions, minimum number of periods | period								2
Telco LLC | Class A-1
Noncontrolling Interest [Line Items]
Preferred interest issued													$ 2,000
Initial preferred distribution percentage								4.25%
Distribution reset period								7 years
Telco LLC | Class A-2 and Class A-3
Noncontrolling Interest [Line Items]
Preferred interest issued			$ 5,250
Initial preferred distribution percentage								6.85%
Period post issuance date that preferred interests can be called at issue price								7 years
Telco LLC | Class A-4 | Subsequent Event
Noncontrolling Interest [Line Items]
Preferred interest issued				$ 2,250
Initial preferred distribution percentage				5.94%