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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Amount of liability recognized for present obligation requiring transfer or otherwise providing economic benefit to others.

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-Topic 860
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 1A
-Subparagraph (b)(1)(ii)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481420/860-30-50-1A

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Topic 860
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 1A
-Subparagraph (b)(2)
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-URI https://asc.fasb.org/1943274/2147481420/860-30-50-1A

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Variable Interest Entities - Narrative (Details) - USD ($) $ in Millions	Jun. 30, 2025	Dec. 31, 2024	Dec. 31, 2007
Variable Interest Entity [Line Items]
Assets	$ 45,746	$ 43,759
Liabilities	27,422	26,372
Transfers accounted for as secured borrowings, carrying amount			$ 398
Transfers accounted for as secured borrowings, associated liabilities, carrying amount			$ 338
Cash and cash equivalents	$ 778	855
SP Fiber
Variable Interest Entity [Line Items]
Percentage ownership	100.00%
GPS
Variable Interest Entity [Line Items]
Ownership percentage in joint venture	48.00%
Variable interest entity, primary beneficiary
Variable Interest Entity [Line Items]
Assets	$ 1,355	1,218
Liabilities	640	353
Transfers accounted for as secured borrowings, carrying amount	389	387
Transfers accounted for as secured borrowings, associated liabilities, carrying amount	334	333
Cash and cash equivalents	5	2
Variable interest entity, primary beneficiary \| GPS
Variable Interest Entity [Line Items]
Cash and cash equivalents	3	2
Variable interest entity, primary beneficiary \| Recourse
Variable Interest Entity [Line Items]
Liabilities	294	5
Variable interest entity, primary beneficiary \| Asset pledged as collateral
Variable Interest Entity [Line Items]
Assets	$ 892	$ 765