Operating Segments and Related Information (Details 4) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019	Sep. 30, 2019	Dec. 31, 2018
Segment Reporting, Asset Reconciling Item [Line Items]
BU assets (accounts receivable, inventory and demo assets, Net)	$ 816,071	$ 737,805
BU assets (accounts receivable, inventory, demo assets and goodwill, Net)	2,166,718	2,102,401
Cash and cash equivalents	319,995	284,592	$ 295,391	$ 512,144
Prepaid expenses and other current assets	92,620	86,337
Property and equipment, net	255,457	255,905
Deferred Income Tax Assets, Net	37,902	39,983
Goodwill	1,350,647	1,364,596
Intangible assets, net	211,206	247,514
Other assets	129,014	120,809
Assets	3,212,912	3,137,541
Defense Technologies
Segment Reporting, Asset Reconciling Item [Line Items]
BU assets (accounts receivable, inventory and demo assets, Net)	395,752	332,639
Goodwill	710,482	728,697
Industrial Technologies
Segment Reporting, Asset Reconciling Item [Line Items]
BU assets (accounts receivable, inventory and demo assets, Net)	420,319	405,166
Goodwill	$ 640,165	$ 635,899

BU assets (accounts receivable, inventory and demonstration assets, Net)

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BU assets (accounts receivable, inventory, demo assets and goodwill, Net)

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Other Assets, Noncurrent, Including Unallocated Assets from Acquisitions

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Prepaid expenses and other current assets, excluding demo assets

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Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Amount, after allocation of valuation allowances and deferred tax liability, of deferred tax asset attributable to deductible differences and carryforwards, with jurisdictional netting.

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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