Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (a)(3)
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

This element represents the amount of earnings or loss of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
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- Definition

This element represents the amount of revenue of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

+ References

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- Definition

The amount of identifiable intangible assets recognized as of the acquisition date.

+ References

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- Definition

Amount recognized as of the acquisition date for the identifiable assets acquired in excess of (less than) the aggregate liabilities assumed.

+ References

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- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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Acquisitions (EME) (Details) - USD ($) $ in Thousands		12 Months Ended
Acquisitions (EME) (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Business Acquisition [Line Items]
Goodwill		$ 182,185	$ 121,829	$ 68,253
SL Industries, Inc. (SLI) \| Electromagnetic Enterprise (EME)
Business Acquisition [Line Items]
Net assets acquired	$ 62,575
Goodwill	30,645
Other intangibles	28,370
Net sales of the acquired business included in the consolidated statement of operations		15,900
Operating income (loss) of the acquired business included in the consolidated statement of operations		$ 100
Customer relationships \| SL Industries, Inc. (SLI) \| Electromagnetic Enterprise (EME)
Business Acquisition [Line Items]
Other intangibles	$ 27,200
Weighted-average amortization life	15 years
Production backlog
Business Acquisition [Line Items]
Weighted-average amortization life		3 months 18 days
Production backlog \| SL Industries, Inc. (SLI) \| Electromagnetic Enterprise (EME)
Business Acquisition [Line Items]
Other intangibles	$ 1,200