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SEGMENT INFORMATION Reconciliation of assets (Details) - USD ($) $ in Thousands	Jul. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Segment reporting disclosures
Total consolidated assets		$ 232,842	$ 301,030
Services \| Westinghouse
Segment reporting disclosures
Accounts receivable	$ 4,700
Operating segments \| Mechanical Solutions
Segment reporting disclosures
Total consolidated assets		67,360	89,545
Operating segments \| Electrical Solutions
Segment reporting disclosures
Total consolidated assets		38,435	68,747
Operating segments \| Services
Segment reporting disclosures
Total consolidated assets		111,792	122,640
Non-allocated corp HQ
Segment reporting disclosures
Total consolidated assets		$ 15,255	$ 20,098