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Acquisitions (Schedule of Acquired Intangible Assets) (Details) - USD ($) $ in Thousands | Feb. 13, 2020 | Jan. 15, 2020 | Aug. 30, 2019
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Delta Separations |  |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |  |
Fair Value, finite-lived intangible assets acquired | $ 13,000 |  |
Delta Separations | Trademarks |  |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |  |
Fair Value, finite-lived intangible assets acquired | 6,000 |  |
Delta Separations | Technology |  |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |  |
Fair Value, finite-lived intangible assets acquired | $ 3,200 |  |
Estimated Useful Life | 10 years |  |
Delta Separations | Customer relationships |  |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |  |
Fair Value, finite-lived intangible assets acquired | $ 3,200 |  |
Estimated Useful Life | 11 years |  |
Delta Separations | Non-compete agreements |  |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |  |
Fair Value, finite-lived intangible assets acquired | $ 300 |  |
Estimated Useful Life | 5 years |  |
Delta Separations | Backlog |  |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |  |
Fair Value, finite-lived intangible assets acquired | $ 300 |  |
Estimated Useful Life | 3 months |  |
Thermo Energy Systems |  |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |  |
Fair Value, finite-lived intangible assets acquired |  | $ 9,750 |
Thermo Energy Systems | Trademarks |  |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |  |
Fair Value, finite-lived intangible assets acquired |  | $ 660 |
Estimated Useful Life |  | 3 years |
Thermo Energy Systems | Technology |  |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |  |
Fair Value, finite-lived intangible assets acquired |  | $ 2,639 |
Estimated Useful Life |  | 15 years |
Thermo Energy Systems | Customer relationships |  |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |  |
Fair Value, finite-lived intangible assets acquired |  | $ 6,451 |
Estimated Useful Life |  | 10 years |
Apeks |  |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |  |
Fair Value, finite-lived intangible assets acquired |  |  | $ 3,000
Apeks | Trademarks |  |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |  |
Fair Value, finite-lived intangible assets acquired |  |  | 1,400
Apeks | Technology |  |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |  |
Fair Value, finite-lived intangible assets acquired |  |  | $ 900
Estimated Useful Life |  |  | 7 years
Apeks | Customer relationships |  |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |  |
Fair Value, finite-lived intangible assets acquired |  |  | $ 700
Estimated Useful Life |  |  | 6 years

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