Debt - Repurchase Agreement (Details) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2023	Dec. 31, 2022
Debt Instrument [Line Items]
Equipment installment plan receivables	$ 1,127	$ 1,211
Repurchase Agreement
Debt Instrument [Line Items]
Maximum borrowing capacity	200
Amount repaid during the period	60
Amounts borrowed and outstanding	0
Amount available for use	200
Repurchase Agreement \| Assets pledged
Debt Instrument [Line Items]
Equipment installment plan receivables	$ 532
Lender's cost of funds \| Repurchase Agreement
Debt Instrument [Line Items]
Contractual spread	1.35%

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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