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

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

Amount of intangible assets, excluding goodwill, acquired at 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.

+ References

No definition available.

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Business Combinations Business Combinations (Details)	3 Months Ended		12 Months Ended
Business Combinations Business Combinations (Details)	Mar. 31, 2019 USD ($)	Mar. 31, 2018 USD ($) 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	$ 8,954,000	$ 0	$ 8,954,000
Goodwill, Impairment Loss	0
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			5300
Goodwill			$ 6,400,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill	$ 0
Other insignificant acquisitions [Member]
Business Acquisition [Line Items]
Business Combination, Consideration Transferred			$ 2,800,000
Number of Businesses Acquired			3