Stock Price Increase, Percentage

No definition available.

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- Definition

Amount, after adjustment, of cost-method investment. Adjustments include, but are not limited to, dividends received in excess of earnings after date of investment that are considered a return of investment and other than temporary impairments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.12)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 325
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=75025870&loc=d3e40691-111596

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 325
-SubTopic 20
-Section 35
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=75027002&loc=d3e40346-111594

+ Details

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- Definition

Original amount of cost-method investments at the acquisition date.

+ References

No definition available.

+ Details

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- Definition

This item represents an other than temporary decline in value that has been recognized against an investment accounted for under the cost method of accounting. The excess of the carrying amount over the fair value of the investment represents the amount of the write down which is or was reflected in earnings. The written down value is a new cost basis with the adjusted value of the investment becoming its new carrying value. Evidence of a loss in value might include, but would not necessarily be limited to, absence of an ability to recover the carrying amount of the investment or inability of the investee to sustain an earnings capacity which would justify the carrying amount of the investment.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 325
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=75025870&loc=d3e40691-111596

+ Details

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- Definition

The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Amount after tax, before reclassification adjustments, of unrealized holding gain (loss) on available-for-sale securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 10A
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=84228862&loc=SL7669646-108580

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=84228862&loc=d3e637-108580

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Balance Type:	credit
Period Type:	duration

- Definition

Aggregate cash proceeds received from a combination of transactions that are classified as investing activities in which assets, which may include one or more investments, are sold to third-party buyers. This element can be used by entities to aggregate proceeds from all asset sales that are classified as investing activities.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- 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.

+ Details

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- Definition

The reporting entity's maximum amount of exposure to loss as a result of its involvement with the Variable Interest Entity (VIE).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph b
-URI http://asc.fasb.org/extlink&oid=77990344&loc=d3e5728-111685

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=77990344&loc=d3e5747-111685

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- Details

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Investments in Other Equity Securities (Details) - USD ($)	3 Months Ended					12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Apr. 01, 2016	Apr. 03, 2015	Dec. 31, 2016	Dec. 31, 2014	Oct. 22, 2014	Sep. 02, 2014
Schedule of Cost-method Investments [Line Items]
Cost Method Investments, Carrying Value	$ 3,600,000	$ 4,400,000				$ 4,400,000
Vislink plc [Member]
Schedule of Cost-method Investments [Line Items]
Cost Method Investments, Original Cost									$ 3,300,000
Cost-method Investments, Other than Temporary Impairment	500,000		$ 1,200,000	$ 1,500,000
Stock Price Increase, Percentage		67.00%
Cost Method Investments, Carrying Value		$ 800,000				800,000
Other Comprehensive Income (Loss), Unrealized Holding Gain (Loss) on Securities Arising During Period, Net of Tax						$ 300,000
Noncontrolling Interest, Ownership Percentage by Parent									3.30%
VJU Gmbh [Member]
Schedule of Cost-method Investments [Line Items]
Cost Method Investments, Original Cost							$ 2,500,000
Cost-method Investments, Other than Temporary Impairment					$ 2,500,000
Noncontrolling Interest, Ownership Percentage by Parent							19.80%
Proceeds from Sales of Assets, Investing Activities	6,000
EDC [Member]
Schedule of Cost-method Investments [Line Items]
Cost Method Investments, Original Cost								$ 3,500,000
Noncontrolling Interest, Ownership Percentage by Parent								18.40%
Cost-method Investments [Member] \| Variable Interest Entity, Not Primary Beneficiary [Member] \| EDC [Member]
Schedule of Cost-method Investments [Line Items]
Variable Interest Entity, Reporting Entity Involvement, Maximum Loss Exposure, Amount	3,600,000
Other Expense [Member] \| Variable Interest Entity, Not Primary Beneficiary [Member] \| EDC [Member]
Schedule of Cost-method Investments [Line Items]
Variable Interest Entity, Reporting Entity Involvement, Maximum Loss Exposure, Amount	$ 100,000