Business Segment Information (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013 segment	Sep. 30, 2012	Dec. 31, 2012
Business Segment Information
Number of reporting segments			2
Revenue:
Total revenue	$ 439.0	$ 447.8	$ 1,287.3	$ 1,274.1
Operating Income (Loss):
Total operating income	31.5	60.3	87.2	116.8
Assets:
Total assets	1,936.2		1,936.2		1,856.4
Scientific Instruments
Revenue:
Total revenue	410.6	408.9	1,198.5	1,184.0
Operating Income (Loss):
Total operating income	33.8	48.0	84.0	106.3
Assets:
Total assets	1,878.6		1,878.6		1,786.2
Energy and Supercon Technologies
Revenue:
Total revenue	32.5	42.4	100.8	98.4
Operating Income (Loss):
Total operating income	(0.8)	14.4	6.7	13.4
Assets:
Total assets	136.9		136.9		134.4
Corporate, eliminations and other
Revenue:
Product and service revenue between reportable segments	(4.1)	(3.5)	(12.0)	(8.3)
Operating Income (Loss):
Total operating income	(1.5)	(2.1)	(3.5)	(2.9)
Assets:
Total assets	$ (79.3)		$ (79.3)		$ (64.2)