Operating Segments and Related Information (Details 4) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Segment Reporting, Asset Reconciling Item [Line Items]
Segment assets (accounts receivable, net and inventories)	$ 737,337	$ 723,391
Segment Reporting Information goodwill	920,364	801,406
Surveillance
Segment Reporting, Asset Reconciling Item [Line Items]
Segment assets (accounts receivable, net and inventories)	278,535	283,324
Segment Reporting Information goodwill	258,480	152,383
Instruments
Segment Reporting, Asset Reconciling Item [Line Items]
Segment assets (accounts receivable, net and inventories)	125,942	114,681
Segment Reporting Information goodwill	151,799	147,595
Security
Segment Reporting, Asset Reconciling Item [Line Items]
Segment assets (accounts receivable, net and inventories)	83,493	93,174
Segment Reporting Information goodwill	106,785	102,983
OEM & Emerging Markets [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Segment assets (accounts receivable, net and inventories)	141,568	144,862
Segment Reporting Information goodwill	254,592	252,647
Maritime [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Segment assets (accounts receivable, net and inventories)	73,963	61,494
Segment Reporting Information goodwill	100,724	97,860
Detection
Segment Reporting, Asset Reconciling Item [Line Items]
Segment assets (accounts receivable, net and inventories)	33,836	25,856
Segment Reporting Information goodwill	$ 47,984	$ 47,938