Line Of Credit Facility, Maximum Increase In Borrowing Capacity

No definition available.

Name:	fls_LineOfCreditFacilityMaximumIncreaseInBorrowingCapacity
Namespace Prefix:	fls_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910

+ Details

Name:	us-gaap_LineOfCredit
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

+ References

+ Details

Name:	us-gaap_LineOfCreditFacilityCurrentBorrowingCapacity
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

Name:	us-gaap_LineOfCreditFacilityLineItems
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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3291-108585

+ Details

Name:	us-gaap_RepaymentsOfDebt
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3291-108585

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

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- Details

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- Details

Name:	us-gaap_DebtInstrumentAxis=fls_TermLoanFacilityMember
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- Details

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Balance Type:
Period Type:

- Details

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- Details

Name:	us-gaap_CreditFacilityAxis=us-gaap_LetterOfCreditMember
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Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=us-gaap_BridgeLoanMember
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Period Type:

- Details

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Debt and Finance Lease Obligations (Senior Credit Facility) (Details) - USD ($)			12 Months Ended
	Sep. 16, 2019	Jul. 16, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Line of Credit Facility [Line Items]
Repayments of debt			$ 105,000,000	$ 60,000,000	$ 60,000,000
Revolving Credit Facility
Line of Credit Facility [Line Items]
Amount outstanding			0	0
Current borrowing capacity			711,500,000	513,700,000
Senior Credit Facility
Line of Credit Facility [Line Items]
Letters of credit, amount outstanding			88,500,000	92,900,000
Term Loan
Line of Credit Facility [Line Items]
Repayments of debt			30,000,000.0	$ 60,000,000	$ 60,000,000.0
Debt repayment			$ 105,000,000.0
Revolving Credit Facility \| New Senior Credit Facility
Line of Credit Facility [Line Items]
Maximum borrowing capacity		$ 800,000,000.0
Maximum increase in borrowing capacity		400,000,000.0
Amount outstanding		75,000,000.0
Repayments of debt	$ 75,000,000.0
Commitment fee percentage			0.20%
Letter of Credit \| New Senior Credit Facility
Line of Credit Facility [Line Items]
Maximum borrowing capacity		750,000,000.0
Bridge Loan \| New Senior Credit Facility
Line of Credit Facility [Line Items]
Maximum borrowing capacity		$ 30,000,000.0
London Interbank Offered Rate (LIBOR) \| Revolving Credit Facility \| New Senior Credit Facility
Line of Credit Facility [Line Items]
Basis spread on variable rate		1.375%
Base Rate \| Revolving Credit Facility \| New Senior Credit Facility
Line of Credit Facility [Line Items]
Basis spread on variable rate		0.375%
Minimum \| Revolving Credit Facility \| New Senior Credit Facility
Line of Credit Facility [Line Items]
Unused capacity, commitment fee percentage		0.09%
Minimum \| London Interbank Offered Rate (LIBOR) \| Revolving Credit Facility \| New Senior Credit Facility
Line of Credit Facility [Line Items]
Basis spread on variable rate		1.00%
Minimum \| Base Rate \| Revolving Credit Facility \| New Senior Credit Facility
Line of Credit Facility [Line Items]
Basis spread on variable rate		0.00%
Maximum \| Revolving Credit Facility \| New Senior Credit Facility
Line of Credit Facility [Line Items]
Unused capacity, commitment fee percentage		0.30%
Maximum \| London Interbank Offered Rate (LIBOR) \| Revolving Credit Facility \| New Senior Credit Facility
Line of Credit Facility [Line Items]
Basis spread on variable rate		1.75%
Maximum \| Base Rate \| Revolving Credit Facility \| New Senior Credit Facility
Line of Credit Facility [Line Items]
Basis spread on variable rate		0.75%