Represents the period of extension to the maturity of debt instrument.

No definition available.

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Represents the number of extensions to the maturity of debt instrument.

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No definition available.

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- Definition

Represents the facility fee that is payable quarterly on the full amount of the commitments under the facility based on the entity's current credit ratings.

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No definition available.

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- Definition

Represents the amount of additional borrowing capacity under the credit facility.

+ References

No definition available.

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- Definition

Represents the amount of the borrowing capacity under the credit facility used to back up outstanding commercial paper borrowings.

+ References

No definition available.

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- Definition

Represents the aggregate amount of default by the entity on other indebtedness subject to the cross-default provisions of the credit facility agreement.

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No definition available.

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- Definition

Represents of Line Of Credit Facility Debt To Capital Ratio Covenant Compliance

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No definition available.

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Represents the maximum debt to capital ratio allowable under the financial covenant.

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No definition available.

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- Definition

The average effective interest rate on short term debt during the reporting period.

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No definition available.

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- Definition

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

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No definition available.

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The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

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No definition available.

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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.

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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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- 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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 19, 22
-Article 5

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- Definition

The cash outflow paid to third parties in connection with debt origination, which will be amortized over the remaining maturity period of the associated long-term debt.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (e)
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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
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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.

+ References

No definition available.

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Weighted average interest rate of short-term debt outstanding.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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For the form of debt having an initial term of less than one year or less than the normal operating cycle, if longer, average borrowings during the period.

+ References

No definition available.

+ Details

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For the form of debt having an initial term of less than one year or less than the normal operating cycle, if longer, maximum month-end borrowings during the period.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section S99
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-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Publisher SEC
-Name Industry Guide
-Number 3
-Section VII
-Subsection 2

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SHORT-TERM BORROWINGS (Details) $ in Thousands		12 Months Ended
SHORT-TERM BORROWINGS (Details) $ in Thousands	Oct. 20, 2014 USD ($) item	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)	Oct. 19, 2014 USD ($)
Short-Term Borrowings
Short-term borrowings		$ 25,000	$ 44,000
Average borrowings outstanding		48,900	30,000
Highest month-end balances		$ 97,000	$ 77,000
Weighted average interest rate during period (as a percent)		0.54	0.38
Weighted average interest rate at year end (as a percent)		0.84%	0.44%
Debt issuance costs		$ 818	$ 651	$ 1,879
Commercial paper
Short-Term Borrowings
Short-term borrowings		25,000
Outstanding borrowings		0
Amount of credit facility used to back up outstanding commercial paper borrowings		25,000
Unsecured revolving credit facility
Short-Term Borrowings
Outstanding borrowings		$ 0
Unsecured revolving credit facility	$ 200,000				$ 150,000
Maturity term	5 years
Number of extensions \| item	2
Extension period	1 year
Facility fee is payable quarterly on the full amount of the commitments under the facility based on our current credit ratings (as a percent)		0.175%
Debt issuance costs		$ 300
Maximum percentage of total indebtedness to total capitalization under the financial covenants of the credit facility agreement		65.00%
Percentage of total indebtedness to total capitalization under the financial covenants of the credit facility agreement		53.00%
Aggregate amount of default on other indebtedness subject to cross-default under the terms of the credit facility.		$ 25,000
Unsecured revolving credit facility \| Federal fund effective rate
Short-Term Borrowings
Margin over the base rate (as a percent)		0.50%
Unsecured revolving credit facility \| One month LIBOR
Short-Term Borrowings
Description of interest rate basis		one month LIBOR
Margin over the base rate (as a percent)		1.00%
Unsecured revolving credit facility \| One month, two month or three month LIBOR
Short-Term Borrowings
Description of interest rate basis		one month, two month, three month or six month LIBOR
Margin over the base rate (as a percent)		1.025%
Letters of credit
Short-Term Borrowings
Unsecured revolving credit facility	$ 20,000
Additional borrowing capacity		$ 75,000
Swingline loan
Short-Term Borrowings
Unsecured revolving credit facility	$ 20,000