Revenues Disaggregated Revenues (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Aug. 31, 2020	Aug. 31, 2019	Aug. 31, 2020	Aug. 31, 2019
Disaggregation of Revenue [Line Items]
Revenues	$ 203,372	$ 236,190	$ 416,664	$ 525,313
Industrial [Member]
Disaggregation of Revenue [Line Items]
Revenues	67,112	139,352	197,220	304,152
Transmission and Distribution [Member]
Disaggregation of Revenue [Line Items]
Revenues	97,619	56,686	146,676	128,967
Power Generation [Member]
Disaggregation of Revenue [Line Items]
Revenues	$ 38,641	$ 40,152	$ 72,768	$ 92,194

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130543-203045

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130545-203045

Name:	us-gaap_RevenueFromContractWithCustomerExcludingAssessedTax
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration