Summary of Significant Accounting Policies - Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Summary of Significant Accounting Policies
Redemption value adjustment	$ 0.0	$ 0.0
Net income (loss) per common share attributable to Bruker Corporation shareholders:
Net income attributable to Bruker Corporation, as reported	$ 157.8	$ 197.2	$ 179.7
Weighted average shares outstanding:
Weighted average shares outstanding-basic	153.4	155.2	156.2
Effect of dilutive securities:
Stock options and restricted stock awards and units (in shares)	1.2	1.4	1.0
Weighted-average number of common shares used in computing diluted net income per common share	154.6	156.6	157.2
Net income per common share attributable to Bruker Corporation shareholders:
Basic (in dollars per share)	$ 1.03	$ 1.27	$ 1.15
Diluted (in dollars per share)	$ 1.02	$ 1.26	$ 1.14