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.

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The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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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.

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Percentage of voting equity interests acquired at the acquisition date in the business combination.

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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Amount of increase in assets, excluding financial assets, lacking physical substance with a definite life, from an acquisition.

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Amount of cash restricted as to withdrawal or usage. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits.

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Goodwill And Intangibles (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended			9 Months Ended
	Sep. 30, 2019	Mar. 31, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Business Acquisition [Line Items]
Restricted cash	$ 2,789			$ 2,789
Goodwill arising from acquisition				9,426
Amortization expense	3,617		$ 1,982	10,581	$ 5,821
Genesis Systems Group
Business Acquisition [Line Items]
Percentage of business acquired						100.00%
Working capital adjustment		$ 448
Padtec SA, Submarine Networks Division
Business Acquisition [Line Items]
Purchase price		19,560
Restricted cash	2,789	2,934		2,789
Goodwill arising from acquisition		9,426
Licenses \| Padtec SA, Submarine Networks Division
Business Acquisition [Line Items]
Restricted cash	$ 1,801	1,956		$ 1,801
Production know-how \| Padtec SA, Submarine Networks Division
Business Acquisition [Line Items]
Acquired finite-lived intangible assets		$ 4,825
Weighted average useful life of acquired intangible assets		6 years
Customer relationships \| Padtec SA, Submarine Networks Division
Business Acquisition [Line Items]
Acquired finite-lived intangible assets		$ 4,825
Weighted average useful life of acquired intangible assets		6 years