Increase (decrease) 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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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- References

No definition available.

+ Details

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- References

No definition available.

+ Details

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

- 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.

+ References

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-Publisher FASB
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+ Details

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

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Balance Type:
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- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

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Namespace Prefix:
Data Type:	na
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- Details

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- Details

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- Details

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- Details

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REVENUE RECOGNITION, Disaggregated Revenues (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Jun. 30, 2021
REVENUE RECOGNITION [Abstract]
Minimum number of days for accounts receivable from tariff contract customers	25 days
Increase (decrease) in reserve for bad debt		$ 500		$ (300)
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	$ 2,230	1,516	$ 1,413
Total Tariff Revenue	90,859	88,141	83,595
Tariff Revenue [Member]
Disaggregation of Revenue [Abstract]
Total Tariff Revenue	82,248	81,050	76,637
Tariff Revenue [Member] \| Consumption Charges [Member]
Disaggregation of Revenue [Abstract]
Total Tariff Revenue	47,924	47,145	45,451
Tariff Revenue [Member] \| Fixed Fees [Member]
Disaggregation of Revenue [Abstract]
Total Tariff Revenue	27,977	27,109	26,216
Tariff Revenue [Member] \| Service Charges [Member]
Disaggregation of Revenue [Abstract]
Total Tariff Revenue	579	351	617
Tariff Revenue [Member] \| DSIC [Member]
Disaggregation of Revenue [Abstract]
Total Tariff Revenue	5,093	4,997	4,331
Tariff Revenue [Member] \| Industrial Wastewater Services [Member]
Disaggregation of Revenue [Abstract]
Total Tariff Revenue	675	1,448	22
Non-Tariff Revenue [Member]
Disaggregation of Revenue [Abstract]
Total Tariff Revenue	6,381	5,575	5,545
Non-Tariff Revenue [Member] \| Service Line Protection Plans [Member]
Disaggregation of Revenue [Abstract]
Total Tariff Revenue	4,594	4,381	4,177
Non-Tariff Revenue [Member] \| Contract Operations [Member]
Disaggregation of Revenue [Abstract]
Total Tariff Revenue	884	840	1,122
Non-Tariff Revenue [Member] \| Design and Installation [Member]
Disaggregation of Revenue [Abstract]
Total Tariff Revenue	562	88	0
Non-Tariff Revenue [Member] \| Inspection Fees [Member]
Disaggregation of Revenue [Abstract]
Total Tariff Revenue	$ 341	$ 266	$ 246