Financial Instruments - Derivative Instruments Fair Value (Details) - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022
Derivative [Line Items]
Derivative Assets Subject to Master Netting Agreement	$ 21	$ 25
Derivative liabilities	(1)	(1)
Total	20	24
Foreign Exchange Forward \| Unrealized appreciation on foreign currency forward contracts
Derivative [Line Items]
Derivative Assets Subject to Master Netting Agreement	21	25
Foreign Exchange Forward \| Unrealized depreciation on foreign currency forward contracts
Derivative [Line Items]
Derivative liabilities	$ (1)	$ (1)

Fair value, after effect of master netting arrangement, of financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and contract can be net settled by means outside contract or delivery of asset. Includes derivative subject to master netting arrangement not elected or qualified to offset. Excludes derivative not subject to master netting arrangement or similar agreement.

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Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

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