Amount of cash paid to acquire the entity.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141R

-Paragraph 68

-Subparagraph f(1)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 51

-Subparagraph d

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

- Definition

The 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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Namespace Prefix:	us-gaap_
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Balance Type:	na
Period Type:	instant

- Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
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- 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_
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Balance Type:	na
Period Type:	duration

- Definition

Decrease for amounts repaid on the credit facility for the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(f))

-URI http://asc.fasb.org/extlink&oid=6881521&loc=d3e23780-122690

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph f

-Article 4

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Balance Type:	credit
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- 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

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 129

-Paragraph 2, 4

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.19(b),22(b))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

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Balance Type:	credit
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- 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://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 470

-SubTopic 10

-Section 45

-Paragraph 13

-URI http://asc.fasb.org/extlink&oid=6743817&loc=d3e1314-112600

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 470

-SubTopic 10

-Section 45

-Paragraph 14

-URI http://asc.fasb.org/extlink&oid=6743817&loc=d3e1336-112600

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-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 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 6

-Paragraph 9, 10, 11

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Line-of-Credit Arrangement

-URI http://asc.fasb.org/extlink&oid=6517033

+ Details

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

- Definition

Debt Instrument, Maturity, Month and Year

+ References

No definition available.

+ Details

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Namespace Prefix:	wso_
Data Type:	xbrli:gYearMonthItemType
Balance Type:	na
Period Type:	instant

- Definition

Line Of Credit Facility Multicurrency Borrowing Sublimit

+ References

No definition available.

+ Details

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Namespace Prefix:	wso_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Line Of Credit Facility Term

+ References

No definition available.

+ Details

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Namespace Prefix:	wso_
Data Type:	xbrli:positiveIntegerItemType
Balance Type:	na
Period Type:	duration

- Definition

Capitalized loan costs paid to bank, lawyers, etc. associated with revolving credit agreement.

+ References

No definition available.

+ Details

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Namespace Prefix:	wso_
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Balance Type:	credit
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Debt - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	1 Months Ended	12 Months Ended
	Apr. 27, 2012	Dec. 31, 2012	Dec. 31, 2011
Debt Instrument [Line Items]
Line of credit facility repayments	$ 72,000
Multicurrency borrowing sublimit	75,000
Commitment fee percentage on unused portion of the commitment		0.15%
Fees paid related to entering revolving credit agreement		2,116	38
Outstanding amount under revolving credit agreement		316,182
Minimum
Debt Instrument [Line Items]
Commitment fee percentage on unused portion of the commitment		0.125%
Maximum
Debt Instrument [Line Items]
Commitment fee percentage on unused portion of the commitment		0.40%
Scenario 1
Debt Instrument [Line Items]
Basis spread		1.125%
Scenario 1 \| Minimum
Debt Instrument [Line Items]
Basis spread		1.00%
Scenario 1 \| Maximum
Debt Instrument [Line Items]
Basis spread		2.75%
Scenario 2
Debt Instrument [Line Items]
Basis spread		0.125%
Scenario 2 \| Minimum
Debt Instrument [Line Items]
Basis spread		0.00%
Scenario 2 \| Maximum
Debt Instrument [Line Items]
Basis spread		1.75%
Swingline Subfacility
Debt Instrument [Line Items]
Revolving credit agreement maximum borrowing capacity	65,000
Letter of Credit
Debt Instrument [Line Items]
Revolving credit agreement maximum borrowing capacity	50,000
New Revolving Credit Facility
Debt Instrument [Line Items]
Revolving credit agreement maximum borrowing capacity	500,000
Credit facility, term	5
Fees paid related to entering revolving credit agreement		2,116
Revolving credit agreement maturity date	2017-04
New Revolving Credit Facility \| Line of Credit
Debt Instrument [Line Items]
Outstanding amount under revolving credit agreement		316,182
Previous Revolving Credit Facility
Debt Instrument [Line Items]
Revolving credit agreement maximum borrowing capacity		300,000
Credit facility, term		5
Previous Carrier Enterprise I Secured Revolving Credit Agreement
Debt Instrument [Line Items]
Revolving credit agreement maximum borrowing capacity		125,000
Credit facility, term		3
Carrier Enterprise III
Debt Instrument [Line Items]
Payment for the acquisition of Carrier Enterprise III	$ 82,000