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

No definition available.

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- Definition

The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

+ References

No definition available.

+ Details

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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=34725769&loc=d3e28878-108400

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399

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Period Type:	instant

- 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/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28551-108399

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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

- Definition

The effective interest rate at the end of the reporting period.

+ References

+ Details

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

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

- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

+ Details

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

- Definition

Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-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 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-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=6879938&loc=d3e572229-122910

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 20, 22
-Article 5

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

+ References

No definition available.

+ Details

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

- Definition

The percentage of amortization of the carrying value of the debt instrument in the next rolling twelve months following the latest balance sheet.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The percentage of amortization of the carrying value of the debt instrument in the fourth and fifth fiscal year following the latest fiscal year.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The percentage of amortization of the carrying value of the debt instrument in the second and third fiscal year following the latest fiscal yea

+ References

No definition available.

+ Details

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Namespace Prefix:	wts_
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- Definition

The percentage points added to the specified reference rate to compute the variable rate on the debt instrument, in addition to the percentage points added regardless of specified reference rate.

+ References

No definition available.

+ Details

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- Definition

Represents the maximum amount of the guarantees available through letters of credit.

+ References

No definition available.

+ Details

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Namespace Prefix:	wts_
Data Type:	xbrli:monetaryItemType
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- Details

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Debt (Details) - USD ($) $ in Millions			6 Months Ended
Debt (Details) - USD ($) $ in Millions	Apr. 28, 2016	Feb. 12, 2016	Jul. 03, 2016	Dec. 31, 2015
Credit Agreement
Long-term Debt			$ 606.6	$ 576.2
Borrowings outstanding			606.6	$ 576.2
5.85% Senior notes due 2016
Credit Agreement
Long-term Debt	$ 225.0
Interest rate (as a percent)	5.85%
Borrowings outstanding	$ 225.0
Interest rate (as a percent)	5.85%
Credit Agreement
Credit Agreement
Term of debt		5 years
Sublimit on letters of credit		$ 100.0
Unused and available credit under the credit agreement			245.1
Amount drawn	$ 230.0
Stand-by letters of credit outstanding			$ 24.9
Eurocurrency rate loans \| LIBOR \| Minimum
Credit Agreement
Interest rate added to base rate (as a percent)			0.975%
Eurocurrency rate loans \| LIBOR \| Maximum
Credit Agreement
Interest rate added to base rate (as a percent)			1.45%
Base rate loans and swing line loans \| LIBOR
Credit Agreement
Interest rate added to base rate (as a percent)			1.00%
Base rate loans and swing line loans \| LIBOR \| Minimum
Credit Agreement
Interest rate added to base rate (as a percent)			0.00%
Base rate loans and swing line loans \| LIBOR \| Maximum
Credit Agreement
Interest rate added to base rate (as a percent)			0.45%
Base rate loans and swing line loans \| Federal funds
Credit Agreement
Interest rate added to base rate (as a percent)			0.50%
Variable interest rate basis			federal funds rate
Base rate loans and swing line loans \| Prime Rate
Credit Agreement
Variable interest rate basis			prime rate
Senior unsecured revolving credit facility
Credit Agreement
Multi-currency borrowing capacity		$ 500.0
Interest rate on revolving credit facility (as a percent)			1.88%
Term loan facility
Credit Agreement
Term of debt		5 years
Interest rate on term loan facility (as a percent)			2.12%
First year (as a percent)		0.00%
Second and third years (as a percent)		7.50%
Fourth and fifth years (as a percent)		10.00%
Amount drawn		$ 300.0
Long-term Debt			$ 300.0
Borrowings outstanding			$ 300.0
Face amount		$ 300.0
Term loan facility \| LIBOR \| Minimum
Credit Agreement
Interest rate added to base rate (as a percent)		1.125%
Term loan facility \| LIBOR \| Maximum
Credit Agreement
Interest rate added to base rate (as a percent)		1.75%