Earnings (Loss) per Common Share - Additional Information (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	9 Months Ended
Sep. 29, 2017	Sep. 30, 2016
Computation Of Earnings Per Share Line Items
Repurchase of common stock	$ 370	$ 1,634
Common Stock Repurchase Plan
Computation Of Earnings Per Share Line Items
Shares repurchased	14
Repurchase of common stock	$ 400
Shares repurchased, average cost per share	$ 26.41

Computation of earnings per share.

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- Definition

The cash outflow to reacquire common stock during the period.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
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- Definition

Number of shares that have been repurchased and retired during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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- Definition

Total cost of shares repurchased divided by the total number of shares repurchased.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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