Debt Instrument, Notes At Price

No definition available.

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
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+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

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

+ References

+ Details

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Period Type:	instant

- Definition

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.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Period remaining on line of credit facility before it terminates, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

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.

+ References

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

+ Details

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Period Type:	duration

- 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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Weighted average interest rate of long-term debt outstanding calculated over time.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
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- Definition

Amount of cash outflow for cost from early extinguishment and prepayment of debt. Includes, but is not limited to, third-party cost, premium paid, and other fee paid to lender directly for debt extinguishment or debt prepayment. Excludes accrued interest.

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Balance Type:	credit
Period Type:	duration

- Definition

The cash inflow from a borrowing with the highest claim on the assets of the entity in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle, if longer).

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Balance Type:	debit
Period Type:	duration

- Definition

Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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Period Type:	instant

- Details

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- Details

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- Details

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- Details

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Debt (Narrative) (Details) - USD ($)	6 Months Ended		12 Months Ended
Debt (Narrative) (Details) - USD ($)	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018	Mar. 31, 2019	Feb. 11, 2019
Debt Instrument [Line Items]
Debt Instrument, Face Amount	$ 4,447,000,000		$ 4,300,000,000
Borrowings under long-term notes	496,855,000	$ 0
Payment for Debt Extinguishment or Debt Prepayment Cost	8,270,000	$ 0
Long term debt	4,407,793,000		4,270,869,000
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Long term debt			0
Commercial Paper [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	197,000,000		$ 0
Line of Credit Facility, Maximum Borrowing Capacity	$ 1,000,000,000.0
Long-term Debt, Weighted Average Interest Rate, over Time	2.70%		2.30%
Commercial Paper [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt Instrument, Term	397 days
4.85% Notes Due 2049 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	$ 500,000,000.0		$ 0	$ 500,000,000.0
Debt Instrument, Interest Rate, Stated Percentage	4.85%			4.85%
Debt Instrument, Notes At Price	99.371%
Borrowings under long-term notes	$ 491,500,000
Payment for Debt Extinguishment or Debt Prepayment Cost	8,300,000
6.55% Notes due 2019 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	$ 0		550,000,000		$ 550,000,000.0
Debt Instrument, Interest Rate, Stated Percentage	6.55%				6.55%
Notes Payable to Banks [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	$ 500,000,000.0
Unused commitment fee	0.10%
Line of Credit Facility, Expiration Period	364 days
Short-term Debt	$ 0
Notes Payable to Banks [Member] \| Revolving Credit Facility [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Unused commitment fee	0.075%
Notes Payable to Banks [Member] \| Revolving Credit Facility [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Unused commitment fee	0.125%
Senior Notes [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	$ 1,000,000,000.0
Unused commitment fee	0.125%
Long term debt	$ 0
Obligation for letters of credit	$ 3,500,000		$ 6,800,000
Senior Notes [Member] \| Revolving Credit Facility [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Unused commitment fee	0.075%
Senior Notes [Member] \| Revolving Credit Facility [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Unused commitment fee	0.20%
London Interbank Offered Rate (LIBOR) [Member] \| Notes Payable to Banks [Member] \| Revolving Credit Facility [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate	1.00%
London Interbank Offered Rate (LIBOR) [Member] \| Notes Payable to Banks [Member] \| Revolving Credit Facility [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate	1.25%
London Interbank Offered Rate (LIBOR) [Member] \| Senior Notes [Member] \| Revolving Credit Facility [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate	0.875%
London Interbank Offered Rate (LIBOR) [Member] \| Senior Notes [Member] \| Revolving Credit Facility [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate	1.50%