Debt (Narrative) (Long-Term Debt) (Details) - USD ($)	1 Months Ended	12 Months Ended
Sep. 30, 2018	Jan. 29, 2022
Debt Instrument [Line Items]
2022		$ 0
2023		0
2024		0
2025		0
2026		0
Notes due 2028 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount		$ 500,000,000
Interest rate		4.45%
Debt Issuance Costs, Gross	$ 5,000,000
Proceeds from Debt, Net of Issuance Costs	$ 495,000,000
Debt Instrument, Redemption Price, Percentage		100.00%
Debt Instrument, Redemption Price, Control Triggering Percentage		101.00%
Notes Due 2030 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount		$ 650,000,000
Interest rate		1.95%
Debt Instrument, Unamortized Discount		$ 8,000,000
Proceeds from Debt, Net of Issuance Costs		$ 642,000,000
Debt Instrument, Redemption Price, Percentage		100.00%
Debt Instrument, Redemption Price, Control Triggering Percentage		101.00%

Debt Instrument, Redemption Price, Control Triggering Percentage

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Face (par) amount of debt instrument at time of issuance.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

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Amount, after accumulated amortization, of debt discount.

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Amount, before accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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The cash inflow from additional borrowings, net of cash paid to third parties in connection with debt origination.

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