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Stock Repurchase Program - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jul. 01, 2017	Jun. 30, 2018	Jul. 01, 2017	Sep. 11, 2018	Sep. 01, 2015
Class of Stock [Line Items]
Stock Repurchase Program, Remaining Authorized Repurchase Amount	$ 1,900		$ 1,900
Average cost per share	0	0	198,000	0
Treasury Stock Acquired, Average Cost Per Share	$ 0.00	$ 0.00	$ 84.14	$ 0.00
Value of shares repurchased	$ 0	$ 0	$ 16,490	$ 0
2013 Repurchase Program | Common Stock
Class of Stock [Line Items]
Number of common shares authorized to be repurchased under new stock repurchase program						5,000,000
2018 Repurchase Program | Subsequent Event | Common Stock
Class of Stock [Line Items]
Number of common shares authorized to be repurchased under new stock repurchase program					5,000,000.0

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The number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan.

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Amount remaining of a stock repurchase plan authorized.

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 30
-Section 45
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Number of shares that have been repurchased during the period and are being held in treasury.

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-Topic 505
-SubTopic 10
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Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

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