Aggregate dividends paid during the period for each share of common stock outstanding.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480008/505-10-S99-1

+ Details

Name:	us-gaap_CommonStockDividendsPerShareCashPaid
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:perShareItemType
Balance Type:	na
Period Type:	duration

- Definition

Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

+ Details

Name:	us-gaap_CommonStockSharesIssued
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount of cash outflow to satisfy grantee's tax withholding obligation for award under share-based payment arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 15
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482740/230-10-45-15

+ Details

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

- Definition

Amount of cash inflow from issuance of shares under share-based payment arrangement. Includes, but is not limited to, option exercised.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 14
-Subparagraph (a)
-SubTopic 10
-Topic 230
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482740/230-10-45-14

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 2A
-Subparagraph (a)
-SubTopic 10
-Topic 718
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480429/718-10-50-2A

+ Details

Name:	us-gaap_ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlansIncludingStockOptions
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The cash inflow from the issuance of common stock, preferred stock, treasury stock, stock options, and other types of equity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 14
-Subparagraph (a)
-SubTopic 10
-Topic 230
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482740/230-10-45-14

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 946
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 3
-Subparagraph (SX 210.6-03(i)(1))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479886/946-10-S99-3

+ Details

Name:	us-gaap_ProceedsFromIssuanceOrSaleOfEquity
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of cash inflow from exercise of option under share-based payment arrangement.

+ References

+ Details

Name:	us-gaap_ProceedsFromStockOptionsExercised
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Number of shares used to settle grantee's tax withholding obligation for award under share-based payment arrangement.

+ References

No definition available.

+ Details

Name:	us-gaap_SharesPaidForTaxWithholdingForShareBasedCompensation
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Available for sale under AT-the-Market offering program.

+ References

No definition available.

+ Details

Name:	wso_AvailableForSaleUnderAtmOfferingProgram
Namespace Prefix:	wso_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Direct costs.

+ References

No definition available.

+ Details

Name:	wso_DirectCosts
Namespace Prefix:	wso_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Maximum aggregate offering amount of stock.

+ References

No definition available.

+ Details

Name:	wso_MaximumAggregateOfferingAmountOfStock
Namespace Prefix:	wso_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Number of shares sold under atm.

+ References

No definition available.

+ Details

Name:	wso_NumberOfSharesSoldUnderAtm
Namespace Prefix:	wso_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Stockholders Equity Note [Line Items]

+ References

No definition available.

+ Details

Name:	wso_StockholdersEquityNoteLineItems
Namespace Prefix:	wso_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	wso_ProgramNameAxis=wso_ATMProgramMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_AwardTypeAxis=us-gaap_EmployeeStockOptionMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementClassOfStockAxis=us-gaap_CommonClassBMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_AwardTypeAxis=us-gaap_RestrictedStockMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementClassOfStockAxis=wso_CommonAndClassBCommonStockMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementEquityComponentsAxis=us-gaap_CommonStockMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_AwardTypeAxis=wso_EmployeeStockPurchasePlanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Shareholders' Equity - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended		6 Months Ended
	Feb. 25, 2022	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Stockholders Equity Note [Line Items]
Shares withheld as payment for tax withholdings related to share based compensation, market value				$ 2,254	$ 2,179
ATM Program [Member]
Stockholders Equity Note [Line Items]
Maximum aggregate offering amount of stock	$ 300,000
Number of shares sold under ATM		45,000
Net proceeds from the sale of Common stock				15,179
Direct costs				375
Available for sale under ATM Program		$ 284,745		$ 284,745
Common stock, issued		45,000		45,000
Employee Stock Option [Member]
Stockholders Equity Note [Line Items]
Shares withheld as payment for tax withholdings related to share based compensation, shares				17,392
Shares withheld as payment for tax withholdings related to share based compensation, market value				$ 5,383
Class B Common Stock \| Restricted Stock
Stockholders Equity Note [Line Items]
Shares withheld as payment for tax withholdings related to share based compensation, shares			8,181		8,181
Shares withheld as payment for tax withholdings related to share based compensation, market value			$ 2,179		$ 2,179
Common and Class B Common Stock
Stockholders Equity Note [Line Items]
Cash dividends paid per share of Common and Class B common stock		$ 2.45	$ 2.2	$ 4.9	$ 4.15
Common and Class B Common Stock \| Restricted Stock
Stockholders Equity Note [Line Items]
Shares withheld as payment for tax withholdings related to share based compensation, shares				6,047
Shares withheld as payment for tax withholdings related to share based compensation, market value				$ 1,664
Common Stock \| Employee Stock Option [Member]
Stockholders Equity Note [Line Items]
Net proceeds from the sale of Common stock		$ 4,526	$ 3,267	12,694	$ 7,222
Shares withheld as payment for tax withholdings related to share based compensation, shares		1,737
Shares withheld as payment for tax withholdings related to share based compensation, market value		$ 595
Common Stock \| Employee Stock Purchase Plan [Member]
Stockholders Equity Note [Line Items]
Net proceeds from shares purchased under ESPP		$ 554	$ 541	$ 1,133	$ 1,006