Assets Leased or Available for Lease [Abstract]

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CPED Proposed Penalty, Per Offense, Per Day

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Public Utilities, Service Area

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Real Estate Selling Expenses

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Value of property contributed in noncash investing and financing activities.

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The difference between the carrying value and the sale price of real estate or properties that were intended to be sold or held for capital appreciation or rental income. This element refers to the gain (loss) included in earnings and not to the cash proceeds of the sale. This element is a noncash adjustment to net income when calculating net cash generated by operating activities using the indirect method.

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Aggregate of the carrying amounts as of the balance sheet date of investments in building and building improvements.

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Amount before accumulated depletion of real estate held for productive use, excluding land held for sale.

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Carrying value of land held for sale.

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Percentage investment held by members or limited partners of limited liability company (LLC) or limited partnership (LP).

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- Definition

Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due 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 required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due 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.

+ References

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due 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 required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due 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 required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due 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 of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due 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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No definition available.

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- Definition

Cash received from the sale of real estate that is held for investment, that is, it is part of an investing activity during the period.

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The amount of property, by major property class, net of accumulated depreciation, subject to or available for lease as of the balance sheet date.

+ References

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No definition available.

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Useful life on which depreciation was computed for entities with a substantial portion of business acquiring and holding investment real estate, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount of real estate investment property which may include the following: (1) land available-for-sale; (2) land available-for-development; (3) investments in building and building improvements; (4) tenant allowances; (5) developments in-process; (6) rental properties; and (7) other real estate investments.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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Summary of Significant Accounting Policies (Real Estate Investments) (Details)			3 Months Ended	12 Months Ended
	Sep. 14, 2018 USD ($)	Apr. 06, 2017 USD ($)	Dec. 31, 2019 USD ($) mi²	Dec. 31, 2019 USD ($) mi²	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Components of Real Estate Investments [Abstract]
Land			$ 14,168,000	$ 14,168,000	$ 13,262,000
Buildings and improvements			43,531,000	43,531,000	43,074,000
Total real estate investment			57,699,000	57,699,000	56,336,000
Proceeds from sale of real estate held-for-investment			745,000
Gain on sale of real estate investments				929,000	0	$ 6,903,000
Operating Leases, Future Minimum Payments Receivable [Abstract]
2017			4,520,000	4,520,000
2018			3,208,000	3,208,000
2019			2,527,000	2,527,000
2020			2,564,000	2,564,000
2021			2,645,000	2,645,000
Thereafter			$ 10,544,000	$ 10,544,000
CA Undeveloped Land
Components of Real Estate Investments [Abstract]
Proceeds from sale of real estate held-for-investment		$ 1,350,000
Gain on sale of real estate investments		580,000
Selling expense		14,000
Minimum [Member]
Schedule of Investments [Line Items]
Service area in square miles \| mi²			246	246
CPED Proposed Penalty, Per Offense, Per Day	$ 500
Components of Real Estate Investments [Abstract]
Estimated useful life				7 years
Maximum [Member]
Schedule of Investments [Line Items]
CPED Proposed Penalty, Per Offense, Per Day	$ 50,000
Components of Real Estate Investments [Abstract]
Estimated useful life				39 years
Land and Building [Member]
Assets Leased or Available for Lease [Abstract]
Assets leased or available for lease			$ 56,839,000	$ 56,839,000	$ 56,090,000
Connecticut Water Company [Member]
Components of Real Estate Investments [Abstract]
Gain on sale of real estate investments				$ 4,000
444 West Santa Clara Street, L.P. [Member]
Components of Real Estate Investments [Abstract]
Limited partership interest percentage				70.00%
444 West Santa Clara Street, L.P. [Member] \| 444 West Santa Clara Street
Components of Real Estate Investments [Abstract]
Proceeds from sale of real estate held-for-investment		11,000,000
Gain on sale of real estate investments		6,323,000
Selling expense		1,157,000
Maine Water Company [Member]
Components of Real Estate Investments [Abstract]
Conservation easement, value			1,200,000	$ 1,200,000
Proceeds from sale of real estate held-for-investment				600,000
Contribution of Property				600,000
Gain on sale of real estate investments				$ 180,000
Parent [Member]
Components of Real Estate Investments [Abstract]
Gain on sale of real estate investments			521,000
Parent [Member] \| 444 West Santa Clara Street
Components of Real Estate Investments [Abstract]
Gain on sale of real estate investments		4,427,000
Noncontrolling Interest [Member]
Components of Real Estate Investments [Abstract]
Gain on sale of real estate investments			$ 224,000
Noncontrolling Interest [Member] \| 444 West Santa Clara Street
Components of Real Estate Investments [Abstract]
Gain on sale of real estate investments		$ 1,896,000