Increase in reserve for bad debt.

No definition available.

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- Definition

Minimum number of days services invoiced in advance beginning of every month for customer, 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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- Definition

The minimum number of days due for accounts receivable after invoicing from regulated contract customers, 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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- Definition

The minimum number of days due for accounts receivable after invoicing from Service Line Protection Plans (SLP) customers, 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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- Definition

The total amount of revenue recognized for the period from rental income and other revenue.

+ References

No definition available.

+ Details

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- Definition

Amount of increase (decrease) in revenue recognized for cumulative catch-up adjustment from contract modification which (increases) decreases obligation to transfer good or service to customer for which consideration from customer has been received or is due.

+ References

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- References

No definition available.

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- References

No definition available.

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- Definition

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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REVENUE RECOGNITION, Disaggregated Revenues (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
REVENUE RECOGNITION [Abstract]
Refund to customers through reduced tariff rates	$ 3,800
Minimum number of days for accounts receivable from tariff contract customers		25 days
Increase in reserve for bad debt		$ 500
Minimum number of days due for accounts receivable from SLP Plan customer		25 days
Minimum number of days customers services invoiced in advance		30 days
Disaggregation of Revenue [Abstract]
Other Operating Revenue not in scope of ASC 606		$ 1,516	$ 1,413	$ 1,271
Total Tariff Revenue		88,141	83,595	80,411
Tariff Revenue [Member]
Disaggregation of Revenue [Abstract]
Total Tariff Revenue		81,050	76,637	73,585
Tariff Revenue [Member] \| Consumption Charges [Member]
Disaggregation of Revenue [Abstract]
Total Tariff Revenue		47,145	45,451	47,747
Tariff Revenue [Member] \| Fixed Fees [Member]
Disaggregation of Revenue [Abstract]
Total Tariff Revenue		27,109	26,216	25,557
Tariff Revenue [Member] \| Service Charges [Member]
Disaggregation of Revenue [Abstract]
Total Tariff Revenue		351	617	718
Tariff Revenue [Member] \| DSIC [Member]
Disaggregation of Revenue [Abstract]
Total Tariff Revenue		4,997	4,331	2,797
Tariff Revenue [Member] \| Industrial Wastewater Services [Member]
Disaggregation of Revenue [Abstract]
Total Tariff Revenue		1,448	22	0
Tariff Revenue [Member] \| Revenue Reserved for Refund - TCJA Impact [Member]
Disaggregation of Revenue [Abstract]
Total Tariff Revenue		0	0	(3,234)
Non-Tariff Revenue [Member]
Disaggregation of Revenue [Abstract]
Total Tariff Revenue		5,575	5,545	5,555
Non-Tariff Revenue [Member] \| Service Line Protection Plans [Member]
Disaggregation of Revenue [Abstract]
Total Tariff Revenue		4,381	4,177	3,992
Non-Tariff Revenue [Member] \| Contract Operations [Member]
Disaggregation of Revenue [Abstract]
Total Tariff Revenue		840	1,122	1,352
Non-Tariff Revenue [Member] \| Design and Installation [Member]
Disaggregation of Revenue [Abstract]
Total Tariff Revenue		88	0	0
Non-Tariff Revenue [Member] \| Inspection Fees [Member]
Disaggregation of Revenue [Abstract]
Total Tariff Revenue		$ 266	$ 246	$ 211