Operating Segments and Related Information Operating Segments and Related Information (Details 2) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenue - External Customers	$ 369,380	$ 389,329	$ 720,923	$ 737,912
Intersegment revenue	0	0	0	0
Earnings (loss) from operations	59,364	70,272	101,814	139,402
Surveillance
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenue - External Customers	105,777	147,859	222,978	265,847
Intersegment revenue	1,568	1,347	3,983	3,177
Earnings (loss) from operations	18,935	34,076	39,296	67,975
Instruments
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenue - External Customers	83,968	80,262	168,023	158,812
Intersegment revenue	173	702	474	2,223
Earnings (loss) from operations	21,037	22,920	41,486	42,944
OEM & Emerging Markets
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenue - External Customers	58,988	48,633	112,790	98,919
Intersegment revenue	5,390	6,824	10,556	12,839
Earnings (loss) from operations	17,613	12,217	29,324	26,639
Maritime
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenue - External Customers	55,230	54,679	107,805	105,140
Intersegment revenue	836	0	1,504	0
Earnings (loss) from operations	9,714	9,374	18,544	17,481
Security
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenue - External Customers	44,735	34,451	74,045	63,922
Intersegment revenue	2,735	0	4,390	0
Earnings (loss) from operations	5,886	3,247	7,572	7,636
Detection
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenue - External Customers	20,682	23,445	35,282	45,272
Intersegment revenue	39	59	59	1,724
Earnings (loss) from operations	3,152	3,899	1,353	6,445
Other
Segment Reporting, Revenue Reconciling Item [Line Items]
Intersegment revenue	(10,741)	(8,932)	(20,966)	(19,963)
Earnings (loss) from operations	$ (16,973)	$ (15,461)	$ (35,761)	$ (29,718)