Operating Segments and Related Information Operating Segments and Related Information (Details 2) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenue - External Customers	$ 351,542	$ 348,583
Intersegment revenue	0	0
Earnings (loss) from operations	42,451	69,130
Surveillance
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenue - External Customers	117,201	117,987
Intersegment revenue	2,415	1,830
Earnings (loss) from operations	20,361	33,726
Instruments
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenue - External Customers	84,056	78,550
Intersegment revenue	302	1,521
Earnings (loss) from operations	20,450	20,024
OEM & Emerging Markets
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenue - External Customers	53,801	50,285
Intersegment revenue	5,166	6,016
Earnings (loss) from operations	11,711	14,596
Maritime
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenue - External Customers	52,575	50,462
Intersegment revenue	668	0
Earnings (loss) from operations	8,830	8,107
Security
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenue - External Customers	29,309	29,472
Intersegment revenue	1,655	0
Earnings (loss) from operations	1,686	4,389
Detection
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenue - External Customers	14,600	21,827
Intersegment revenue	21	1
Earnings (loss) from operations	(1,800)	2,545
Other
Segment Reporting, Revenue Reconciling Item [Line Items]
Intersegment revenue	(10,227)	(9,368)
Earnings (loss) from operations	$ (18,787)	$ (14,257)