Restricted stock and stock units issued, description.

No definition available.

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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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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- Definition

Percentage of vesting of share-based compensation awards.

+ References

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- Definition

Number of shares issued during the period related to Restricted Stock Awards, net of any shares forfeited.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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(29))
-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 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

Reference 4: 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(28))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Equity-based Compensation - Additional Information (Details) - shares			3 Months Ended
	Feb. 29, 2016	Jan. 04, 2016	Mar. 31, 2017	Apr. 01, 2016
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restricted stock and stock units, granted			7,500	512,650
Restricted stock and stock units issued, description			Of the 512,650 shares granted in 2016, 10,000 were issued out of treasury stock and 502,650 were issued out of the Computer Task Group, Inc. Stock Compensation Employee Trust.
Annual vesting percentage			25.00%	25.00%
Vesting period			4 years	4 years
Stock Vesting, One Year From Grant Date [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Annual vesting percentage			25.00%	25.00%
Stock Vesting, Two Year From Grant Date [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Annual vesting percentage			25.00%	25.00%
Stock Vesting, Three Year From Grant Date [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Annual vesting percentage			25.00%	25.00%
Stock Vesting, Four Year From Grant Date [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Annual vesting percentage			25.00%	25.00%
Treasury Stock [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restricted stock and stock units, issued		10,000
Stock Trusts [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restricted stock and stock units, issued	502,650