Significant Accounting Policies and Accounting Developments (Earnings Per Share) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended																12 Months Ended
	Dec. 31, 2019		Sep. 30, 2019		Jun. 30, 2019		Mar. 31, 2019		Dec. 31, 2018		Sep. 30, 2018		Jun. 30, 2018		Mar. 31, 2018		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Earnings per share:
Net earnings of Flowserve Corporation	$ 69,800		$ 68,400		$ 58,200		$ 57,300		$ 63,100		$ 28,200		$ 13,200		$ 15,100		$ 253,668	$ 119,671	$ 2,652
Dividends on restricted shares not expected to vest																	0	0	0
Earnings attributable to common and participating shareholders																	$ 253,668	$ 119,671	$ 2,652
Weighted average shares:
Common stock (in shares)																	131,012	130,794	130,600
Participating securities (in shares)																	22	29	103
Denominator for basic earnings per common share (in shares)																	131,034	130,823	130,703
Effect of potentially dilutive securities (in shares)																	685	448	655
Denominator for diluted earnings per common share (in shares)																	131,719	131,271	131,358
Net earnings per share attributable to Flowserve Corporation common shareholders:
Basic (in dollars per share)	$ 0.53	[1]	$ 0.52	[1]	$ 0.44	[1]	$ 0.44	[1]	$ 0.48	[1]	$ 0.22	[1]	$ 0.10	[1]	$ 0.12	[1]	$ 1.94	$ 0.91	$ 0.02
Diluted (in dollars per share)	$ 0.53	[1]	$ 0.52	[1]	$ 0.44	[1]	$ 0.44	[1]	$ 0.48	[1]	$ 0.21	[1]	$ 0.10	[1]	$ 0.12	[1]	$ 1.93	$ 0.91	$ 0.02

[1] Earnings per share is computed independently for each of the quarters presented. The sum of the quarters may not equal the total year amount due to the impact of changes in weighted average quarterly shares outstanding.