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Acquisitions (Allocation of Purchase Consideration to the Assets Acquired and Liabilities Assumed) (Details) - USD ($) $ in Thousands | Sep. 30, 2019 | Aug. 30, 2019 | Dec. 31, 2018 | Aug. 21, 2018
--- | --- | --- | --- | ---
Business Acquisition [Line Items] |  |  |  |
Goodwill | $ 327,983 |  | $ 323,671 |
Apeks |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Cash |  | $ 4,149 |  |
Working capital |  | (1,230) |  |
Property, plant and equipment |  | 859 |  |
Acquired intangible assets |  | 5,061 |  |
Other assets |  | 508 |  |
Other liabilities |  | (982) |  |
Goodwill |  | 4,185 |  |
Fair value of purchase consideration |  | $ 12,550 |  |
SolarBOS |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Cash |  |  |  | $ 915
Working capital |  |  |  | 680
Property, plant and equipment |  |  |  | 483
Acquired intangible assets |  |  |  | 1,450
Other assets |  |  |  | 13
Other liabilities |  |  |  | (51)
Goodwill |  |  |  | 2,879
Fair value of purchase consideration |  |  |  | $ 6,369

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- Definition Amount of currency on hand as well as demand deposits with banks or financial institutions, acquired at the acquisition date. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=116869197&loc=d3e4845-128472 + Details
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- Definition Amount of intangible assets, excluding goodwill, acquired at the acquisition date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=116869197&loc=d3e4845-128472 + Details
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- Definition Amount of other assets expected to be realized or consumed after one year or the normal operating cycle, if longer, acquired at the acquisition date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=116869197&loc=d3e4845-128472 + Details
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