Earnings Per Share - Computation (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Earnings Per Share
Net income attributable to Bruker Corporation, as reported	$ 87.1	$ 54.3	$ 201.4	$ 88.9
Weighted average shares outstanding:
Weighted average shares outstanding-basic	151.4	153.2	151.5	153.7
Effect of dilutive securities:
Stock options and restricted stock awards and units (in shares)	1.4	1.1	1.5	1.1
Weighted-average number of common shares used in computing diluted net income per common share	152.8	154.3	153.0	154.8
Net income per common share attributable to Bruker Corporation shareholders:
Basic (in dollars per share)	$ 0.58	$ 0.35	$ 1.33	$ 0.58
Diluted (in dollars per share)	$ 0.57	$ 0.35	$ 1.32	$ 0.57