Business Segment Information (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013 segment	Jun. 30, 2012	Dec. 31, 2012
Business Segment Information
Number of reporting segments			2
Revenue:
Total revenue	$ 454.9	$ 420.7	$ 848.3	$ 826.3
Operating Income (Loss):
Total operating income	43.5	22.1	55.7	56.5
Assets:
Total assets	1,801.8		1,801.8		1,856.4
Scientific Instruments
Revenue:
Total revenue	421.6	397.0	787.9	775.1
Operating Income (Loss):
Total operating income	39.6	23.2	50.2	58.3
Assets:
Total assets	1,740.1		1,740.1		1,786.2
Energy and Supercon Technologies
Revenue:
Total revenue	37.1	26.0	68.3	56.0
Operating Income (Loss):
Total operating income	6.6	(0.7)	7.5	(1.0)
Assets:
Total assets	134.1		134.1		134.4
Corporate, eliminations and other
Revenue:
Product and service revenue between reportable segments	(3.8)	(2.3)	(7.9)	(4.8)
Operating Income (Loss):
Total operating income	(2.7)	(0.4)	(2.0)	(0.8)
Assets:
Total assets	$ (72.4)		$ (72.4)		$ (64.2)