Share Repurchase Program - Additional Information (Detail) - USD ($)	12 Months Ended
Dec. 31, 2015	Sep. 24, 2007
Equity [Abstract]
Stock repurchase program authorized aggregate amount		$ 100,000,000
Share repurchased under share repurchase program (in shares)	300,000
Stock repurchase program total cost	$ 7,071,000
Stock repurchase program average price (in usd per share)	$ 23.57

Total cost of shares repurchased divided by the total number of shares repurchased under a stock repurchase program.

No definition available.

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- References

No definition available.

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- Definition

Amount of stock repurchase plan authorized.

+ References

No definition available.

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

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 04
-Article 3

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 29, 30
-Article 5

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- Definition

Equity impact of the value of stock that has been repurchased and retired during the period. The excess of the purchase price over par value can be charged against retained earnings (once the excess is fully allocated to additional paid in capital).

+ References

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