DEBT (Outstanding Debt Balances) (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Debt, Carrying Value	$ 140,239	$ 149,187
Debt Instrument, Interest Rate, Effective Percentage	4.20%	4.30%
Asset Related Debt
Debt Instrument [Line Items]
Debt, Carrying Value	$ 36,137	$ 44,255
Debt Instrument, Interest Rate, Effective Percentage	3.20%	3.90%
Bond related debt
Debt Instrument [Line Items]
Debt, Due within one year	$ 223	$ 317
Debt, Due after one year	$ 31,414	$ 38,938
Debt Instrument, Interest Rate, Effective Percentage, Current Portion	2.90%	4.00%
Debt Instrument, Interest Rate, Effective Percentage, Noncurrent Portion	2.90%	3.70%
Non-bond related debt
Debt Instrument [Line Items]
Debt, Due within one year	$ 1,500	$ 1,500
Debt, Due after one year	3,000	$ 3,500
Debt, Carrying Value	$ 4,500
Debt Instrument, Interest Rate, Effective Percentage, Current Portion	5.00%	5.00%
Debt Instrument, Interest Rate, Effective Percentage, Noncurrent Portion	5.00%	5.00%
Other Debt
Debt Instrument [Line Items]
Debt, Carrying Value	$ 104,102	$ 104,932
Debt Instrument, Interest Rate, Effective Percentage	4.60%	4.50%
Subordinated Loan
Debt Instrument [Line Items]
Debt, Due within one year	$ 2,218	$ 2,232
Debt, Due after one year	$ 94,945	$ 95,490
Debt Instrument, Interest Rate, Effective Percentage, Current Portion	3.90%	3.70%
Debt Instrument, Interest Rate, Effective Percentage, Noncurrent Portion	3.90%	3.70%
Net Premium and Debt Issuance Costs	$ 7,800	$ 7,900
Notes Payable and Other Debt
Debt Instrument [Line Items]
Debt, Due within one year	0	0
Debt, Due after one year	$ 6,939	$ 7,210
Debt Instrument, Interest Rate, Effective Percentage, Current Portion	0.00%	0.00%
Debt Instrument, Interest Rate, Effective Percentage, Noncurrent Portion	14.80%	14.70%
Unamortized debt issue costs	$ 200	$ 200

Debt Instrument, Interest Rate, Effective Percentage, Current Portion

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- Definition

Debt Instrument, Interest Rate, Effective Percentage, Noncurrent Portion

+ References

No definition available.

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- Definition

Amount of net premiums and debt issuance costs as of the balance sheet date.

+ References

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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

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 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

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+ References

No definition available.

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 3: 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(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

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

+ References

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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

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- 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

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