Consideration From Sale Of Real Estate

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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- Definition

Lessee, Operating Lease, Minimum Monthly Rental

+ References

No definition available.

+ Details

Name:	gcpwi_LesseeOperatingLeaseMinimumMonthlyRental
Namespace Prefix:	gcpwi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Number Of Directors Appointed By Noncontrolling Interest Holder

+ References

No definition available.

+ Details

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Namespace Prefix:	gcpwi_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Reimbursement Of Director Fees

+ References

No definition available.

+ Details

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Namespace Prefix:	gcpwi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Reimbursement Of Director Fees, Maximum

+ References

No definition available.

+ Details

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

- Definition

Term of lessee's operating lease renewal, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918673-209980

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Term of lessee's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

+ Details

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Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	instant

- Definition

The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

+ References

No definition available.

+ Details

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

- Definition

Cash received for the sale of real estate that is not part of an investing activity during the current period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3179-108585

+ Details

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Balance Type:	debit
Period Type:	duration

- Definition

Amount of stock repurchase plan authorized.

+ References

No definition available.

+ Details

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

- Definition

Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21463-112644

Reference 2: 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(29))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
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-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(28))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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Balance Type:	na
Period Type:	duration

- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

+ Details

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- Details

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- Details

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Subsequent Events (Details)					1 Months Ended	3 Months Ended
Subsequent Events (Details)	Aug. 05, 2020 shares	Jul. 31, 2020 USD ($)	Jul. 02, 2020 USD ($)	May 28, 2020 numberOfDirectors	Aug. 05, 2020 USD ($)	Jun. 30, 2020 numberOfDirectors	Jul. 30, 2020 USD ($)
Starboard
Subsequent Event [Line Items]
Number of directors appointed by noncontrolling interest \| numberOfDirectors				8		8
GCP Applied Technologies \| Starboard
Subsequent Event [Line Items]
Noncontrolling interest ownership percentage						9.00%
Subsequent Event
Subsequent Event [Line Items]
Consideration from sale of corporate headquarters		$ 125,000,000.0
Proceeds from sale of corporate headquarters		$ 122,500,000
Lease term			18 months
Lease renewal term			6 months
Minimum monthly rental payments			$ 600,000
Share repurchase program, authorized amount							$ 100,000,000
Stock repurchased (in shares) \| shares	0
Subsequent Event \| Starboard
Subsequent Event [Line Items]
Reimbursement of director fees, maximum			$ 2,000,000.0
Reimbursement of director fees					$ 2,000,000.0