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SHARE-BASED COMPENSATION (Details) - USD ($) $ / shares in Units, $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013
Share-based compensation |  |  |
Number of shares authorized | 3,100,000 |  |
Restricted Stock Units |  |  |
Award activity |  |  |
Outstanding at the beginning of the period (in shares) | 1,368,880 |  |
Granted (in shares) | 269,660 | 232,450 | 313,550
Vested (in shares) | (302,668) |  |
Forfeited (in shares) | (22,322) |  |
Outstanding at the end of the period (in shares) | 1,313,550 | 1,368,880 |
Weighted-Average Grant Date Fair Value |  |  |
Granted (in dollars per share) | $ 35.50 | $ 40.19 | $ 27.71
Other disclosure |  |  |
Fair value of restricted stock awards vested | $ 9,800 | $ 9,400 | $ 1,800
Unrecognized compensation cost | $ 17,100 |  |
Weighted-average period of recognition of unrecognized compensation cost | 2 years |  |
Stock Options |  |  |
Stock options activity |  |  |
Stock options outstanding (in shares) | 0 | 0 | 35,730
Weighted average exercise price (in dollars per share) |  |  | $ 29.10
Exercised (in shares) |  |  | 35,530
Exercised (in dollars per share) |  |  | $ 29.10
Forfeited (in shares) |  |  | 200
Additional disclosures related to the Company's stock option program |  |  |
Intrinsic value of options exercised |  | $ 169 | $ 330
Cash proceeds of options exercised |  | 1,136 | 2,785
Tax benefit of options exercised |  | $ 22 | $ 109
SARs |  |  |
Share-based compensation |  |  |
Granted to date (in shares) | 0 |  |

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- Definition Aggregate proceeds received by the entity during the annual period from exercises of stock or unit options and conversion of similar instruments granted under equity-based payment arrangements. + 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 (j) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition Unrecognized cost of unvested share-based compensation awards. + 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 (i) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition Disclosure of the aggregate tax benefit realized from the exercise of stock options and the conversion of similar instruments during the annual period. + 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 (j) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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