Restructuring Costs (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended		3 Months Ended		6 Months Ended	3 Months Ended	6 Months Ended	3 Months Ended	6 Months Ended	3 Months Ended	6 Months Ended	3 Months Ended	6 Months Ended	3 Months Ended	6 Months Ended	3 Months Ended	6 Months Ended	3 Months Ended	6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014 Total COGS and SGA	Mar. 31, 2014 Total COGS and SGA	Jun. 30, 2014 Total COGS and SGA	Jun. 30, 2014 Surveillance	Jun. 30, 2014 Surveillance	Jun. 30, 2014 Instruments	Jun. 30, 2014 Instruments	Jun. 30, 2014 OEM & Emerging Markets	Jun. 30, 2014 OEM & Emerging Markets	Jun. 30, 2014 Maritime	Jun. 30, 2014 Maritime	Jun. 30, 2014 Security	Jun. 30, 2014 Security	Jun. 30, 2014 Detection	Jun. 30, 2014 Detection	Jun. 30, 2014 Other	Jun. 30, 2014 Other
Restructuring Cost and Reserve [Line Items]
Restructuring expenses	$ 3,547	$ 0	$ 11,361	$ 0	$ 3,547	$ 8,403	$ 11,951	$ 606	$ 4,725	$ 2,672	$ 6,196	$ 109	$ 276	$ 16	$ (125)	$ 0	$ 0	$ 144	$ 759	$ 0	$ 120