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

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- Definition

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

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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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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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Debt and Credit Agreements - Narrative (Details) - USD ($)	Oct. 15, 2019	Sep. 30, 2019	Sep. 12, 2019	Mar. 31, 2019	Feb. 28, 2019
Commercial Paper
Line of Credit Facility
Maximum borrowing capacity of credit facility		$ 1,000,000,000.0
Borrowings outstanding		0
2.40% Notes due 2030
Line of Credit Facility
Debt issued			$ 400,000,000
Debt interest rate percentage			2.40%
3.35% Notes due 2049
Line of Credit Facility
Debt issued			$ 600,000,000
Debt interest rate percentage			3.35%
3.70% Notes Due October 30, 2020 \| Subsequent Event
Line of Credit Facility
Debt interest rate percentage	3.70%
Debt outstanding	$ 500,000,000
4.25% Notes due 2029
Line of Credit Facility
Debt issued					$ 600,000,000
Debt interest rate percentage					4.25%
4.50% Notes due 2049
Line of Credit Facility
Debt issued					$ 400,000,000
Debt interest rate percentage					4.50%
Unsecured Revolving Credit Facility \| Credit Facility
Line of Credit Facility
Maximum borrowing capacity of credit facility				$ 1,000,000,000.0
Unsecured Revolving Credit Facility due 2024 \| Credit Facility
Line of Credit Facility
Maximum borrowing capacity of credit facility				$ 1,200,000,000
Borrowings outstanding		$ 0