Revision to Previously Reported Financial Information - Balance Sheet (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Jun. 30, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Dec. 31, 2018
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Prepaid expenses and other	$ 109,451		$ 106,478
Total current assets	2,806,145		2,506,747
Property, plant and equipment, net of accumulated depreciation	551,011		563,564
Other assets, net of allowance for expected credit losses	241,509		253,054
Total assets	5,173,576		4,938,277
Contract liabilities	198,380		221,095	$ 224,243
Total current liabilities	1,093,582		1,117,442
Retirement obligations and other liabilities	541,721		530,994
Retained earnings	3,625,291		3,652,244
Total Flowserve Corporation shareholders’ equity	1,673,421		1,746,739
Total equity	1,703,843	$ 1,647,172	1,772,341	$ 1,723,394	$ 1,711,979	$ 1,632,002
Total liabilities and equity	$ 5,173,576		4,938,277
As Reported
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Prepaid expenses and other			105,101
Total current assets			2,505,370
Property, plant and equipment, net of accumulated depreciation			572,175
Other assets, net of allowance for expected credit losses			227,185
Total assets			4,919,642
Contract liabilities			216,541
Total current liabilities			1,112,888
Retirement obligations and other liabilities			473,295
Retained earnings			3,695,862
Total Flowserve Corporation shareholders’ equity			1,790,357
Total equity			1,815,959
Total liabilities and equity			4,919,642
Adjustments
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Prepaid expenses and other			1,377
Total current assets			1,377
Property, plant and equipment, net of accumulated depreciation			(8,611)
Other assets, net of allowance for expected credit losses			25,869
Total assets			18,635
Contract liabilities			4,554
Total current liabilities			4,554
Retirement obligations and other liabilities			57,699
Retained earnings			(43,618)		$ (37,800)	$ (28,800)
Total Flowserve Corporation shareholders’ equity			(43,618)
Total equity			(43,618)
Total liabilities and equity			$ 18,635