Debt - Repurchase Agreement (Details) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2022	Dec. 31, 2021
Debt Instrument [Line Items]
Equipment installment plan receivables	$ 1,161	$ 1,085
Repurchase Agreement
Debt Instrument [Line Items]
Maximum borrowing capacity	200
Amount borrowed during the period	110
Amount repaid during the period	50
Outstanding borrowings	60
Unused borrowing capacity	140
Repurchase Agreement \| Assets available to be pledged
Debt Instrument [Line Items]
Equipment installment plan receivables	$ 558
SOFR rate \| Repurchase Agreement
Debt Instrument [Line Items]
Contractual spread	1.25%

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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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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Amortized cost, before allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement and net investment in lease.

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Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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Amount of cash outflow for payment of an obligation from a lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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Carrying value as of the balance sheet date, including the current and noncurrent portions, of collateralized debt obligations (with maturities initially due after one year or beyond the operating cycle, if longer). Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower.

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