Operating Segments and Related Information (Details 4) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Segment Reporting, Asset Reconciling Item [Line Items]
Segment assets (accounts receivable, net and inventories)	$ 694,798	$ 723,391
Segment Reporting Information goodwill	896,436	801,406
Surveillance
Segment Reporting, Asset Reconciling Item [Line Items]
Segment assets (accounts receivable, net and inventories)	269,646	283,324
Segment Reporting Information goodwill	244,433	152,383
Instruments
Segment Reporting, Asset Reconciling Item [Line Items]
Segment assets (accounts receivable, net and inventories)	111,800	114,681
Segment Reporting Information goodwill	148,538	147,595
Security
Segment Reporting, Asset Reconciling Item [Line Items]
Segment assets (accounts receivable, net and inventories)	76,976	93,174
Segment Reporting Information goodwill	103,844	102,983
OEM & Emerging Markets [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Segment assets (accounts receivable, net and inventories)	139,791	144,862
Segment Reporting Information goodwill	253,074	252,647
Maritime [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Segment assets (accounts receivable, net and inventories)	73,619	61,494
Segment Reporting Information goodwill	98,596	97,860
Detection
Segment Reporting, Asset Reconciling Item [Line Items]
Segment assets (accounts receivable, net and inventories)	22,966	25,856
Segment Reporting Information goodwill	$ 47,951	$ 47,938