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- Definition

Share-based compensation arrangement by share-based payment award percentage of shares to be increased before vesting period.

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- Definition

Share-based compensation arrangement by share-based payment award, share performance period.

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- Definition

Share-based compensation arrangement by share-based payment award, share price to be increased before vesting period..

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- Definition

Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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.

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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).

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- Definition

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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- Definition

The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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- Definition

The risk-free interest rate assumption that is used in valuing an option on its own shares.

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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.

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No definition available.

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- Definition

Gross number of share options (or share units) granted during the period.

+ References

No definition available.

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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- Definition

Price of a single share of a number of saleable stocks of a company.

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No definition available.

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- Definition

Percentage of vesting of share-based compensation awards.

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- Definition

Expected term of share-based compensation awards, 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 (f)(2)(i)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.D.2)
-URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809

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- Definition

Weighted average grant-date fair value of options vested.

+ References

No definition available.

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Equity-based Compensation - Additional Information (Details) - $ / shares		3 Months Ended						9 Months Ended
	May 15, 2017	Sep. 29, 2017	Jun. 30, 2017	Mar. 31, 2017	Sep. 30, 2016	Jul. 01, 2016	Apr. 01, 2016	Sep. 29, 2017
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restricted stock and stock units, granted		0	316,165	7,500	0	0	512,650
Stock options granted		0			0	0
Restricted stock, restricted stock units and stock options granted, description								Restricted stock and stock units totaling 512,650 shares were granted in the 2016 first quarter of which 10,000 shares were issued out of treasury stock and 502,650 shares were issued out of the Computer Task Group, Inc. Stock Compensation Employee Trust. No stock option or restricted stock grants were issued during the 2016 second or third quarter.
Performance Shares [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restricted stock and stock units, granted	196,015
Closing price of company's stock granted to senior management			$ 5.75
Expected volatility			36.20%
Expected dividend yield			0.00%
Risk-free rate of return			1.49%
Performance Shares [Member] \| Share-based Compensation Award, Tranche One [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Closing price of company's stock granted to senior management			$ 8.63
Percentage of shares to be increased before vesting period			50.00%
Shares performance period			30 days
Vesting period			3 years
Shares vesting percentage			50.00%
Derived services period			1 year 2 months 20 days
Performance Shares [Member] \| Share-based Compensation Award, Tranche One [Member] \| Binomial Model [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share price to be increased before vesting period			$ 1.63
Performance Shares [Member] \| Stock Vesting, Two Year From Grant Date [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Closing price of company's stock granted to senior management			$ 11.50
Percentage of shares to be increased before vesting period			100.00%
Shares performance period			30 days
Vesting period			3 years
Shares vesting percentage			50.00%
Derived services period			1 year 9 months 15 days
Performance Shares [Member] \| Stock Vesting, Two Year From Grant Date [Member] \| Binomial Model [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share price to be increased before vesting period			$ 0.95
Non Performance Shares [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restricted stock and stock units, granted			120,150
Vesting period			4 years
Shares vesting percentage			25.00%
Non Performance Shares [Member] \| Share-based Compensation Award, Tranche One [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares vesting percentage			25.00%
Non Performance Shares [Member] \| Stock Vesting, Two Year From Grant Date [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares vesting percentage			25.00%
Non Performance Shares [Member] \| Stock Vesting, Three Year From Grant Date [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares vesting percentage			25.00%
Non Performance Shares [Member] \| Stock Vesting, Four Year From Grant Date [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares vesting percentage			25.00%
Treasury Stock [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restricted stock and stock units, granted							502,650
Stock Trusts [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restricted stock and stock units, granted							10,000
Employee Stock Option [Member] \| 2010 Equity Award Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock options granted	24,900
Expected volatility	36.90%
Expected dividend yield	0.00%
Risk-free rate of return	1.81%
Stock options granted. fair value	$ 1.85
Stock option vest, fair value	$ 5.75
Expected term	4 years 2 months 13 days