Annual patronage refund rate

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Refers to the number of existing bonds.

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

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

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

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Weighted average interest rate of debt outstanding.

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No definition available.

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Date the credit facility terminates, in CCYY-MM-DD format.

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No definition available.

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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.

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

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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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No definition available.

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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.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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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.

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

Amount of earnings distributed to patrons of the agricultural cooperative.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 905
-SubTopic 605
-Section 45
-Paragraph 2
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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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DEBT (Details)	12 Months Ended
DEBT (Details)	Dec. 31, 2017 USD ($) Bond	Dec. 31, 2016 USD ($)	Jan. 31, 2018 USD ($)
Long-term debt consists of [Abstract]
Principal amount	$ 106,931,000	$ 103,647,000
Less: current maturities (principal amount)	1,344,000	1,316,000
Total long-term debt	105,587,000	102,331,000
Payments of principal amounts due during the next five years and thereafter [Abstract]
2018	1,344,000
2019	1,371,000
2020	1,401,000
2021	1,432,000
2022	1,133,000
Thereafter	$ 100,251,000
Artesian Water [Member]
Line of Credit Facility [Line Items]
Weighted average interest rate paid on the lines of credit	2.28%
First Mortgage Bonds [Member]
Debt Instrument [Line Items]
Number of existing bonds \| Bond	2
Long-term debt consists of [Abstract]
Principal amount	$ 99,600,000	95,600,000
Payments of principal amounts due during the next five years and thereafter [Abstract]
2018	600,000
2019	600,000
2020	600,000
2021	600,000
2022	600,000
Thereafter	96,600,000
First Mortgage Bonds [Member] \| Subsequent Event [Member]
Long-term debt consists of [Abstract]
Principal amount			$ 25,000,000
First Mortgage Bonds [Member] \| Series O [Member]
Debt Instrument [Line Items]
Debt prepayment costs	$ 4,500,000
Interest rate, stated percentage	8.17%
Maturity date	Dec. 29, 2020
Long-term debt consists of [Abstract]
Principal amount	$ 0	20,000,000
First Mortgage Bonds [Member] \| Series P [Member]
Debt Instrument [Line Items]
Interest rate, stated percentage	6.58%
Maturity date	Jan. 31, 2018
Long-term debt consists of [Abstract]
Principal amount	$ 25,000,000	25,000,000
First Mortgage Bonds [Member] \| Series Q [Member]
Debt Instrument [Line Items]
Interest rate, stated percentage	4.75%
Maturity date	Dec. 01, 2043
Long-term debt consists of [Abstract]
Principal amount	$ 0	15,400,000
First Mortgage Bonds [Member] \| Series R [Member]
Debt Instrument [Line Items]
Interest rate, stated percentage	5.96%
Maturity date	Dec. 31, 2028
Long-term debt consists of [Abstract]
Principal amount	$ 25,000,000	25,000,000
First Mortgage Bonds [Member] \| Series S [Member]
Debt Instrument [Line Items]
Interest rate, stated percentage	4.45%
Maturity date	Dec. 31, 2033
Long-term debt consists of [Abstract]
Principal amount	$ 9,600,000	10,200,000
First Mortgage Bonds [Member] \| Series T [Member]
Debt Instrument [Line Items]
Interest rate, stated percentage	4.24%
Maturity date	Dec. 20, 2036
Long-term debt consists of [Abstract]
Principal amount	$ 40,000,000	0
State revolving fund loans [Member]
Long-term debt consists of [Abstract]
Principal amount	7,331,000	8,047,000
Payments of principal amounts due during the next five years and thereafter [Abstract]
2018	744,000
2019	771,000
2020	801,000
2021	832,000
2022	533,000
Thereafter	$ 3,651,000
State revolving fund loans [Member] \| 4.48%, due 08/01/2021 [Member]
Debt Instrument [Line Items]
Interest rate, stated percentage	4.48%
Maturity date	Aug. 01, 2021
Long-term debt consists of [Abstract]
Principal amount	$ 1,190,000	1,456,000
State revolving fund loans [Member] \| 3.57%, due 09/01/2023 [Member]
Debt Instrument [Line Items]
Interest rate, stated percentage	3.57%
Maturity date	Sep. 01, 2023
Long-term debt consists of [Abstract]
Principal amount	$ 558,000	640,000
State revolving fund loans [Member] \| 3.64%, due 05/01/2025 [Member]
Debt Instrument [Line Items]
Interest rate, stated percentage	3.64%
Maturity date	May 01, 2025
Long-term debt consists of [Abstract]
Principal amount	$ 1,025,000	1,142,000
State revolving fund loans [Member] \| 3.41%, due 02/01/2031 [Member]
Debt Instrument [Line Items]
Interest rate, stated percentage	3.41%
Maturity date	Feb. 01, 2031
Long-term debt consists of [Abstract]
Principal amount	$ 2,315,000	2,448,000
State revolving fund loans [Member] \| 3.40%, due 07/01/2032 [Member]
Debt Instrument [Line Items]
Interest rate, stated percentage	3.40%
Maturity date	Jul. 01, 2032
Long-term debt consists of [Abstract]
Principal amount	$ 2,243,000	2,361,000
Citizens Bank [Member] \| Artesian Resources [Member]
Line of Credit Facility [Line Items]
Line of credit	40,000,000
Available funds under this line of credit	$ 35,900,000
Expiration date of line of credit	May 25, 2018
Citizens Bank [Member] \| LIBOR [Member] \| Artesian Resources [Member]
Line of Credit Facility [Line Items]
Variable rate for credit facility	LIBOR
Interest rate	1.00%
CoBank [Member] \| Artesian Resources [Member]
Line of Credit Facility [Line Items]
Line of credit	$ 20,000,000
Available funds under this line of credit	$ 14,500,000
CoBank [Member] \| Artesian Water [Member]
Line of Credit Facility [Line Items]
Expiration date of line of credit	Jul. 20, 2018
Patronage refunds	$ 0.6	$ 0.7
Annual patronage refund rate	1.00%
CoBank [Member] \| Artesian Water Maryland [Member]
Line of Credit Facility [Line Items]
Line of credit	$ 10,000,000
CoBank [Member] \| LIBOR [Member] \| Artesian Water [Member]
Line of Credit Facility [Line Items]
Variable rate for credit facility	LIBOR
Interest rate	1.50%