Credit facility participation fee and fronting fee percentage.

No definition available.

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Balance Type:	na
Period Type:	duration

- Definition

Amount of amortization expense attributable to debt issuance costs.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
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-Publisher FASB
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-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28555-108399

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- 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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Namespace Prefix:	us-gaap_
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Balance Type:	na
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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.

+ Details

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

- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(2))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

+ Details

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Balance Type:	na
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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Data Type:	xbrli:durationItemType
Balance Type:	na
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- Definition

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

+ References

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Balance Type:	debit
Period Type:	instant

- Definition

The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The effective interest rate at the end of the reporting period.

+ References

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

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

- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- 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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
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+ Details

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

- Definition

The cash outflow for the settlement of obligation drawn from a contractual arrangement with the lender, including letter of credit, standby letter of credit and revolving credit arrangements, under which borrowings can be made up to a specific amount at any point in time with maturities due beyond one year or the operating cycle, if longer.

+ References

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-SubTopic 10
-Section 45
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Balance Type:	credit
Period Type:	duration

- Definition

The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

+ References

+ Details

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- Details

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Long-Term Debt (Narrative) (Details) - USD ($)				1 Months Ended	12 Months Ended
Long-Term Debt (Narrative) (Details) - USD ($)	Jun. 07, 2019	Jun. 27, 2018	Aug. 15, 2015	Feb. 04, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Jul. 01, 2019
Debt Instrument [Line Items]
Long-term debt					$ 10,000,000	$ 10,000,000
Debt Issuance Costs, Net							$ 120,000
Amortization of debt issuance costs					$ 40,000	103,000	$ 51,000
Credit facility participation fee and fronting fee percentage					0.25%
Debt instrument, term			5 years
Debt issuance costs capitalized					$ 266,000
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity			$ 100,000,000					$ 70,000,000
Debt instrument, maturity date		Jun. 27, 2023	Aug. 18, 2020
Repayments of Long-term Lines of Credit	$ 5,000,000			$ 5,000,000
Line of Credit Facility, Remaining Borrowing Capacity					$ 60,000,000
Debt instrument, term		5 years
Revolving Credit Facility [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Line of credit facility, interest rate at period end					0.1875%
Minimum [Member] \| Base Rate [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate					0.00%
Minimum [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate					1.00%
Minimum [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Line of credit facility, commitment fee percentage					0.20%
Maximum [Member] \| Base Rate [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate					1.00%
Maximum [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate					2.00%
Maximum [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Line of credit facility, commitment fee percentage					0.30%
Second Amendment [Member] \| Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Debt Issuance Costs, Net					$ 120,000
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Long-term debt					$ 10,000,000	$ 10,000,000