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

No definition available.

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Data Type:	num:percentItemType
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Period Type:	duration

- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 6
-Subparagraph (a)
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-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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- 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

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Period Type:	duration

- Definition

Date the credit facility terminates, in CCYY-MM-DD format.

+ References

+ Details

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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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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The carrying value as of the balance sheet date of the noncurrent portion 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
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-Section 45
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=99376301&loc=d3e1314-112600

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

The cash outflow paid to third parties in connection with debt origination, which will be amortized over the remaining maturity period of the associated long-term debt.

+ 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 (e)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3291-108585

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Balance Type:	credit
Period Type:	duration

- Definition

Seasonal discretionary maximum borrowing capacity under revolving credit agreement.

+ References

No definition available.

+ Details

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Namespace Prefix:	wso_
Data Type:	xbrli:monetaryItemType
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Debt - Additional Information (Detail) - USD ($)		6 Months Ended	12 Months Ended
Debt - Additional Information (Detail) - USD ($)	Dec. 05, 2018	Mar. 31, 2019	Dec. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Revolving credit agreement, maturity date	Dec. 05, 2023
Payment of fees related to revolving credit agreement				$ 790,000
Borrowings under revolving credit agreement			$ 155,700,000	135,200,000
London Interbank Offer Rate
Debt Instrument [Line Items]
Basis spread			87.50%
Federal Funds Effective Rate [Member]
Debt Instrument [Line Items]
Basis spread			0.50%
Eurocurrency Rate
Debt Instrument [Line Items]
Basis spread			1.00%
Commitment Fee
Debt Instrument [Line Items]
Basis spread			7.50%
Federal Funds and Eurocurrency Rate [Member]
Debt Instrument [Line Items]
Basis spread			0.00%
Maximum \| London Interbank Offer Rate
Debt Instrument [Line Items]
Basis spread			150.00%
Maximum \| Federal Funds Effective Rate [Member]
Debt Instrument [Line Items]
Basis spread			50.00%
Maximum \| Eurocurrency Rate
Debt Instrument [Line Items]
Basis spread			50.00%
Maximum \| Commitment Fee
Debt Instrument [Line Items]
Basis spread			20.00%
Minimum \| London Interbank Offer Rate
Debt Instrument [Line Items]
Basis spread			87.50%
Minimum \| Federal Funds Effective Rate [Member]
Debt Instrument [Line Items]
Basis spread			0.00%
Minimum \| Eurocurrency Rate
Debt Instrument [Line Items]
Basis spread			0.00%
Minimum \| Commitment Fee
Debt Instrument [Line Items]
Basis spread			7.50%
Letter of Credit
Debt Instrument [Line Items]
Maximum capacity under revolving credit agreement			$ 10,000,000
Swingline Subfacility
Debt Instrument [Line Items]
Maximum capacity under revolving credit agreement			100,000,000
Revolving Credit Facility
Debt Instrument [Line Items]
Payment of fees related to revolving credit agreement				$ 790,000
Maximum capacity under revolving credit agreement	$ 500,000,000
Seasonal discretionary maximum borrowing capacity under revolving credit agreement		$ 400,000,000
Alternative Currency Sublimit
Debt Instrument [Line Items]
Maximum capacity under revolving credit agreement			75,000,000
Mexican Borrowing Sublimit
Debt Instrument [Line Items]
Maximum capacity under revolving credit agreement			$ 8,000,000