XML 107 R92.htm IDEA: XBRL DOCUMENT v3.19.3.a.u2

Note 21 - Quarterly Data (Unaudited) (Details Textual) - USD ($) $ in Thousands		1 Months Ended		3 Months Ended					12 Months Ended
	Jul. 27, 2018	Dec. 31, 2018	Aug. 31, 2018	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Dec. 31, 2018	Sep. 30, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Proceeds from Legal Settlements					$ 2,300
Gain (Loss) on Insurance Proceeds									$ 1,641
Business Combination, Bargain Purchase, Gain Recognized, Amount								$ 21,900		$ 20,080
Ameron Water Transmission Group, LLC [Member]
Business Combination, Bargain Purchase, Gain Recognized, Amount	$ 20,080
Business Combination, Bargain Purchase, Increase (Decrease) in Gain Recognized, Measurement Period Adjustment							$ (1,800)
Property in Houston, Texas [Member]
Gain (Loss) on Disposition of Property Plant Equipment, Total			$ 2,800					$ 2,800
Monterrey, Mexico Facility [Member]
Gain (Loss) on Disposition of Property Plant Equipment, Total		$ 200					$ 200
Fire [Member]
Production Related Impairments or Charges, Total				$ 2,700	700	$ 3,200
Business Interruption Insurance Proceeds				4,000	1,000				5,000
Gain (Loss) on Insurance Proceeds				$ 1,200	$ 400				$ 1,600

X

- Definition

In a business combination in which the amount of net identifiable assets acquired and liabilities assumed exceeds the aggregate consideration transferred or to be transferred (as defined) due to measurement period adjustment, this element represents the increase (decrease) amount of gain recognized by the entity.

+ References

No definition available.

+ Details

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Namespace Prefix:	nwpx_
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Balance Type:	credit
Period Type:	duration

X

- Definition

Represents the amount of business interruption insurance proceeds received.

+ References

No definition available.

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Namespace Prefix:	nwpx_
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X

- Definition

Amount of gain (loss) on insurance proceeds during the period.

+ References

No definition available.

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X

- Definition

In a business combination in which the amount of net identifiable assets acquired and liabilities assumed exceeds the aggregate consideration transferred or to be transferred (as defined), this element represents the amount of gain recognized by the entity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
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- Definition

Amount of gain (loss) on sale or disposal of property, plant and equipment assets, including oil and gas property and timber property.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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X

- Definition

Cash received for the settlement of litigation during the current period.

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- Definition

Nonrecurring impairment charges related to the write-off of production-related equipment and inventory. This tag is used when an Entity charges this cost to cost of goods sold.

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