Discontinued Operations	12 Months Ended
Dec. 31, 2018
Discontinued Operations And Disposal Groups [Abstract]
Discontinued Operations	17. DISCONTINUED OPERATIONS The Company’s discontinued operations did not have any sales in 2018, 2017 or 2016. In 2018 and 2017, loss from discontinued operations net of taxes of $0.4 million and $0.9 million, respectively, were primarily related to changes in estimates associated with remediation of formerly owned property in Montana. In 2016, income from discontinued operations of $3.0 million, net of taxes, was primarily a result of payments received from settlement agreements with insurers, and others, in connection with a declaratory action filed in the United States court for the Eastern District of Missouri.

The entire disclosure related to a disposal group. Includes, but is not limited to, a discontinued operation, disposal classified as held-for-sale or disposed of by means other than sale or disposal of an individually significant component.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-URI http://asc.fasb.org/topic&trid=2155823

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-URI http://asc.fasb.org/subtopic&trid=2122178

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