Business Acquisition, Connections of Acquired Business

No definition available.

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- Definition

Business Combination, Consideration Transferred, Shares

+ References

No definition available.

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- Definition

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.

+ References

No definition available.

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- Definition

The amount of goodwill arising from a business combination that is expected to be deductible for tax purposes.

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- Definition

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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- Definition

This element represents a description of how the entity obtained control of the acquired entity.

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- Definition

This element represents the amount of revenue of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

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- Definition

Amount of assets acquired at the acquisition date.

+ References

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- Definition

Amount of assets that are expected to be realized or consumed within one year or the normal operating cycle, if longer, acquired at the acquisition date.

+ References

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- References

No definition available.

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- Definition

Amount of liabilities due within one year or within the normal operating cycle, if longer, assumed at the acquisition date.

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- Definition

Amount of deferred tax asset attributable to deductible temporary differences and carryforwards acquired at the acquisition date.

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- Definition

Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

+ References

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- Definition

The amount of property, plant, and equipment recognized as of the acquisition date.

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- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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- Definition

Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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- Definition

The number of businesses acquired by the entity during the period.

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No definition available.

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Business Combinations Business Combinations (Details)	3 Months Ended	9 Months Ended		12 Months Ended
Business Combinations Business Combinations (Details)	Sep. 30, 2019 USD ($)	Sep. 30, 2019 USD ($)	Sep. 30, 2018 USD ($) shares	Dec. 31, 2018 USD ($)
Business Acquisition [Line Items]
Business Combination, Control Obtained Description				Through the purchase of all of the outstanding shares of Falls Water, NWN Water acquired the net assets and 100% control of Falls Water.
Goodwill	$ 49,333,000	$ 49,333,000	$ 6,563,000	$ 8,954,000
Goodwill, Impairment Loss		0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets [Abstract]
Goodwill	49,333,000	49,333,000	6,563,000	$ 8,954,000
Sunriver [Member]
Business Acquisition [Line Items]
Business Combination, Pro Forma Information, Revenue of Acquiree since Acquisition Date, Actual	1,700,000	2,300,000
Business Combination, Consideration Transferred		$ 55,000,000.0
Business Acquisition, Connections of Acquired Business		9,400
Goodwill	39,912,000	$ 39,912,000
Business Acquisition, Goodwill, Expected Tax Deductible Amount	50,200,000	50,200,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill	0	0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets [Abstract]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets	222,000	222,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment	14,009,000	14,009,000
Goodwill	39,912,000	39,912,000
Business Combination Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Assets	828,000	828,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities	(22,000)	(22,000)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets	$ 54,949,000	54,949,000
Falls Water Co [Member]
Business Acquisition [Line Items]
Business Combination, Consideration Transferred			$ 8,500,000
Business Combination, Consideration Transferred, Shares \| shares			125,000
Business Acquisition, Connections of Acquired Business				5,300
Goodwill				$ 6,200,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill				0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets [Abstract]
Goodwill				6,200,000
Other insignificant acquisitions [Member]
Business Acquisition [Line Items]
Business Combination, Consideration Transferred		$ 1,400,000		$ 2,800,000
Number of Businesses Acquired		2		3