Debt Instrument, Covenant, Debt to Capital Ratio

No definition available.

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- Definition

Line of Credit Facility, Amended Maximum Borrowing Capacity

+ References

No definition available.

+ Details

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- Definition

Notes Issued, Term

+ References

No definition available.

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- Definition

number of days to maturity from date of issue

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No definition available.

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- Definition

Percentage of original payment amount if the notes are required to be repurchased.

+ References

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.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

+ Details

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- Definition

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

+ References

+ Details

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- 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.

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- Definition

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.

+ References

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-Topic 210
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- 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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- 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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- 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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- Definition

Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

+ Details

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- Definition

Including the current and noncurrent portions, carrying value as of the balance sheet date of long-term unsecured obligations issued by corporations and other borrowers to investors (with maturities initially due after one year or beyond the operating cycle if longer).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition

The fair value of notes issued in noncash investing and financing activities.

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+ Details

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- Definition

The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

+ References

No definition available.

+ Details

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- Definition

Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Financing Activities
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- Definition

Indebtedness divided by net capital.

+ References

No definition available.

+ Details

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- Definition

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

+ References

No definition available.

+ Details

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Long-Term Debt And Notes Payable (Narrative) (Details)		1 Months Ended					9 Months Ended	12 Months Ended
Long-Term Debt And Notes Payable (Narrative) (Details)	Feb. 05, 2018 USD ($)	Feb. 28, 2018 USD ($)	Jan. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2013 USD ($)	Nov. 30, 2006 USD ($)	Sep. 30, 2015 USD ($)	Dec. 31, 2017 USD ($)	Feb. 07, 2018 USD ($)	Dec. 31, 2016 USD ($)	Mar. 31, 2013 USD ($)	May 31, 2012 USD ($)	Sep. 30, 2003
Debt Instrument [Line Items]
Line of credit facility, amended maximum borrowing capacity											$ 500,000,000	$ 300,000,000
Long-term debt				$ 494,100,000				$ 494,100,000		$ 745,300,000
Total debt to capitalization ratio				0.36				0.36
Long-term Commercial Paper							$ 500,000,000
number of days to maturity							397
4.45% Notes Due 2023 [Member]
Debt Instrument [Line Items]
Notes issued, term					10 years
Notes issued					$ 300,000,000
Debt instrument interest rate										4.45%
Long-term debt				$ 298,400,000				$ 298,400,000		$ 298,100,000
Percentage of principal amount Company may be required to buy back at					101.00%
Annualized interest rate including debt issuance cost amortization				4.56%				4.56%
Debt Instrument, Face Amount				$ 300,000,000				$ 300,000,000		300,000,000
2.75% Notes Due 2018 [Member]
Debt Instrument [Line Items]
Notes issued					$ 250,000,000
Debt instrument interest rate				2.75%				2.75%
Long-term Debt				$ 250,000,000				$ 250,000,000
Long-term debt										249,200,000
Percentage of principal amount Company may be required to buy back at					101.00%
Annualized interest rate including debt issuance cost amortization				2.92%				2.92%
Debt Instrument, Face Amount				$ 250,000,000				$ 250,000,000		250,000,000
5.50% Notes Due 2013 [Member]
Debt Instrument [Line Items]
Debt instrument interest rate													5.50%
6.55% Notes Due 2036 [Member]
Debt Instrument [Line Items]
Notes issued, term						30 years
Notes issued						$ 200,000,000
Debt instrument interest rate						6.55%
Long-term debt				$ 198,100,000				$ 198,100,000		198,000,000
Percentage of principal amount Company may be required to buy back at						101.00%
Annualized interest rate including debt issuance cost amortization				6.67%				6.67%
Debt Instrument, Face Amount				$ 200,000,000				$ 200,000,000		$ 200,000,000
2017 Facility [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Debt Instrument, Covenant, Debt to Capital Ratio				0.65				0.65
2017 Facility [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Debt Instrument, Covenant, Debt to Capital Ratio				1.00				1.00
Base Rate [Member] \| 2017 Facility [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Basis spread on variable rate				0.00%
Base Rate [Member] \| 2017 Facility [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Basis spread on variable rate				0.50%
Base Rate [Member] \| 364 Day Credit Agreement [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Basis spread on variable rate				0.00%
Base Rate [Member] \| 364 Day Credit Agreement [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Basis spread on variable rate				0.75%
Base Rate [Member] \| 3 Year Term Loan Agreement [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Basis spread on variable rate				0.00%
Base Rate [Member] \| 3 Year Term Loan Agreement [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Basis spread on variable rate				0.75%
London Interbank Offered Rate (LIBOR) [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Basis spread on variable rate								1.05%
London Interbank Offered Rate (LIBOR) [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Basis spread on variable rate								1.475%
London Interbank Offered Rate (LIBOR) [Member] \| 2017 Facility [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Basis spread on variable rate				0.805%
London Interbank Offered Rate (LIBOR) [Member] \| 2017 Facility [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Basis spread on variable rate				1.50%
London Interbank Offered Rate (LIBOR) [Member] \| 364 Day Credit Agreement [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Basis spread on variable rate				0.875%
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage				0.07%
London Interbank Offered Rate (LIBOR) [Member] \| 364 Day Credit Agreement [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Basis spread on variable rate				1.75%
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage				0.25%
London Interbank Offered Rate (LIBOR) [Member] \| 3 Year Term Loan Agreement [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Basis spread on variable rate				0.875%
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage				0.07%
London Interbank Offered Rate (LIBOR) [Member] \| 3 Year Term Loan Agreement [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Basis spread on variable rate				1.75%
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage				0.25%
Federal Funds Rate [Member]
Debt Instrument [Line Items]
Basis spread on variable rate								0.50%
Adjusted London Interbank Offered Rate [Member]
Debt Instrument [Line Items]
Basis spread on variable rate								1.00%
Adjusted London Interbank Offered Rate [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Basis spread on variable rate								0.05%
Adjusted London Interbank Offered Rate [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Basis spread on variable rate								0.475%
Commercial Paper [Member] \| Line of Credit [Member] \| CP Program [Member]
Debt Instrument [Line Items]
Long-term Debt				$ 0				$ 0
Revolving Credit Facility [Member] \| Line of Credit [Member] \| 2017 Facility [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity				550,000,000				550,000,000
Revolving Credit Facility [Member] \| Line of Credit [Member] \| 2013 Facility [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity											$ 500,000,000
Letter of Credit [Member] \| Line of Credit [Member] \| Letter of Credit Reimbursement Agreement [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity				47,000,000				47,000,000
Line of Credit [Member] \| 364 Day Credit Agreement [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity				150,000,000				150,000,000
Long-term Line of Credit				0				0
Line of Credit [Member] \| Line of Credit [Member] \| 3 Year Term Loan Agreement [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity				200,000,000				200,000,000
Long-term Line of Credit				0				0
Standby Letters of Credit [Member] \| Line of Credit [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity				$ 21,000,000				$ 21,000,000
Subsequent Event [Member] \| 2.75% Notes Due 2018 [Member]
Debt Instrument [Line Items]
Debt instrument interest rate									2.75%
Long-term Debt									$ 250,000,000
Subsequent Event [Member] \| Senior Notes [Member] \| Senior Notes Due 2048 [Member]
Debt Instrument [Line Items]
Debt instrument interest rate	4.20%
Debt Instrument, Face Amount	$ 350,000,000
Subsequent Event [Member] \| Commercial Paper [Member] \| Line of Credit [Member] \| CP Program [Member]
Debt Instrument [Line Items]
Proceeds from Issuance of Debt			$ 340,000,000
Subsequent Event [Member] \| Line of Credit [Member] \| 364 Day Credit Agreement [Member]
Debt Instrument [Line Items]
Proceeds from Lines of Credit			100,000,000
Repayments of Debt	$ 100,000,000	$ 100,000,000
Subsequent Event [Member] \| Line of Credit [Member] \| Line of Credit [Member] \| 3 Year Term Loan Agreement [Member]
Debt Instrument [Line Items]
Proceeds from Lines of Credit			$ 200,000,000