Debt (2022 Credit Facility - Narrative) (Details) $ in Millions			6 Months Ended
	Dec. 22, 2022	Aug. 04, 2022 USD ($)	Jun. 30, 2023 USD ($)	Apr. 05, 2023 USD ($)	Dec. 31, 2022 USD ($)	Dec. 22, 2021
Debt Instrument [Line Items]
Subsidiary ownership			100.00%
2022 Revolving Credit Facility | Minimum
Debt Instrument [Line Items]
Line of credit facility, unused capacity, commitment fee percentage	0.15%	0.375%
2022 Revolving Credit Facility | Maximum
Debt Instrument [Line Items]
Line of credit facility, unused capacity, commitment fee percentage	0.275%	0.50%
Ratio of indebtedness to net capital						0.65
Revolving Credit Facility | 2022 Revolving Credit Facility | Line of Credit
Debt Instrument [Line Items]
Maximum borrowing capacity			$ 3,500
Aggregate commitment				$ 3,500
Line of credit facility, increase, net		$ 500
Minimum current ratio		1.00
Leverage ratio, percentage of credit limit		10.00%
Leverage ratio, amount of credit limit		$ 150
Letters of credit			25
Debt Instrument			$ 310		$ 250
Revolving Credit Facility | 2022 Revolving Credit Facility | Line of Credit | On Or After March 31, 2022
Debt Instrument [Line Items]
Leverage ratio		4.00
Revolving Credit Facility | 2022 Revolving Credit Facility | Line of Credit | Secured Overnight Financing Rate (SOFR)
Debt Instrument [Line Items]
Basis points	0.10%	0.10%
Debt instrument, discount coverage ratio	9.00%
Revolving Credit Facility | 2022 Revolving Credit Facility | Line of Credit | Fed Funds Effective Rate Overnight Index Swap Rate
Debt Instrument [Line Items]
Basis points		0.50%
Revolving Credit Facility | 2022 Revolving Credit Facility | Line of Credit | Base Rate
Debt Instrument [Line Items]
Basis points		1.00%
Revolving Credit Facility | 2022 Revolving Credit Facility | Line of Credit | Minimum | Secured Overnight Financing Rate (SOFR)
Debt Instrument [Line Items]
Basis points	1.25%	1.75%
Revolving Credit Facility | 2022 Revolving Credit Facility | Line of Credit | Minimum | Base Rate
Debt Instrument [Line Items]
Basis points	0.25%	0.75%
Revolving Credit Facility | 2022 Revolving Credit Facility | Line of Credit | Maximum | Secured Overnight Financing Rate (SOFR)
Debt Instrument [Line Items]
Basis points	1.875%	2.75%
Revolving Credit Facility | 2022 Revolving Credit Facility | Line of Credit | Maximum | Base Rate
Debt Instrument [Line Items]
Basis points	0.875%	1.75%
Revolving Credit Facility | 2022 Revolving Credit Facility | Long-term debt
Debt Instrument [Line Items]
Minimum interest coverage ratio	1.50
Revolving Credit Facility | 2022 Revolving Credit Facility Five-Year Tranche | Line of Credit
Debt Instrument [Line Items]
Line of credit facility, expiration period			5 years
Aggregate commitment			$ 2,000	$ 2,000