Summary of Significant Accounting Policies - Depreciation and Amortization (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2025	Mar. 31, 2024
Capitalized Contract Cost [Line Items]
Amortization of capitalized contract costs	$ 108	$ 65
Amortization of customer relationships and other intangible assets	153	201
Depreciation of property, plant and equipment	65	67
Total depreciation and amortization	326	333
Contract Cost Fulfillment
Capitalized Contract Cost [Line Items]
Amortization of capitalized contract costs	41	21
Contract Cost, Acquisitions
Capitalized Contract Cost [Line Items]
Amortization of capitalized contract costs	$ 67	$ 44

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Amount of amortization expense for asset recognized from cost incurred to obtain or fulfill contract with customer.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

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The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

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