Notes Receivable and Customers' Advances for Construction (Details) $ in Thousands	12 Months Ended
Dec. 31, 2017 USD ($) Municipality	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Notes Receivable and Customers' Advances for Construction [Abstract]
Number of municipalities with agreements to extend water service \| Municipality	1
Interest income on notes receivable	$ 98	$ 100	$ 110
Interest rate on notes outstanding	7.50%
Amounts Related to Water District Projects Included in Balance Sheet [Abstract]
Notes receivable, including interest	$ 255	255
Customers' advances for construction	306	307
Other customers' advances for construction	$ 6,018	$ 6,795

An amount representing an agreement for an unconditional promise by the maker to pay the Entity (holder) a definite sum of money at a future date more than one year from the balance sheet date, net of any write-downs taken for collection uncertainty on the part of the holder. Such amount may include accrued interest receivable in accordance with the terms of the debt. The debt also may contain provisions and related items including a discount or premium, payable on demand, secured, or unsecured, interest bearing or noninterest bearing, among a myriad of other features and characteristics. This amount does not include amounts related to receivables held-for-sale.

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 210.5-02.17)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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

- Definition

Stated interest rate of notes receivable from time-sharing transactions.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 978
-SubTopic 310
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=68077313&loc=d3e27327-108691

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Balance Type:	na
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- References

No definition available.

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- Definition

For utilities only, represents the carrying amount of the liability related to other projects as of the balance sheet date for payments received by a utility from its customers in advance of performing its obligations under terms of its construction agreements.

+ References

No definition available.

+ Details

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Namespace Prefix:	yorw_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

For utilities only, represents the carrying amount of the liability related to water district projects as of the balance sheet date for payments received by a utility from its customers in advance of performing its obligations under terms of its construction agreements.

+ References

No definition available.

+ Details

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Namespace Prefix:	yorw_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The amount of interest income on notes receivable.

+ References

No definition available.

+ Details

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Namespace Prefix:	yorw_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- References

No definition available.

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Namespace Prefix:	yorw_
Data Type:	xbrli:stringItemType
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- Definition

Number of municipalities the Company has agreement with to extend water service into previously formed water districts.

+ References

No definition available.

+ Details

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Namespace Prefix:	yorw_
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Balance Type:	na
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