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COMMON STOCK (Details) (USD $) | 12 Months Ended
--- | ---
Dec. 31, 2012 | Dec. 31, 2011 | Dec. 31, 2010
Class of Stock [Line Items] |  |  |
Common stock purchased and retired | $ 6,644,000 |  |
Minimum percentage of outstanding common stock held by two shareholders (in hundredths) | 10.00% |  |
Minimum percentage of common stock needs to held by shareholders having more than ten percent of Class A common stock as per class B Protection clause (in hundredths) | 10.00% |  |
Number of days from trigger date to purchase Class B common shares | 90 days |  |
Percentage of common stock held by shareholder one (in hundredths) | 31.60% |  |
Percentage of common stock held by shareholder two (in hundredths) | 13.30% |  |
Percentage shareholding of class B considered as per class B Protection clause | below 10% |  |
Common stock dividends declared | 3,200,000 | 3,200,000 | 3,200,000
Class A [Member] |  |  |
Class of Stock [Line Items] |  |  |
Common stock repurchased during the period (in shares) |  | 0 | 0
Number of shareholders with ownership in excess of ten percent | 2 |  |
Common stock dividends declared each quarter (in dollars per share) | $ 0.06 | $ 0.06 | $ 0.06
Class B [Member] |  |  |
Class of Stock [Line Items] |  |  |
Authorized amount of repurchase of outstanding Class B common shares | 10,000,000 |  |
Common stock purchased and retired (in shares) | 368,723 |  |
Common stock purchased and retired | $ 6,600,000 |  |
Common stock repurchased during the period (in shares) |  | 0 | 0
Common stock dividends declared each quarter (in dollars per share) | $ 0.07 | $ 0.07 | $ 0.07

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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 SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 29, 30 -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 12 -Paragraph 10 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Article 3 Reference 4: 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 + Details
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- Definition Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Research Bulletin (ARB) -Number 43 -Section B -Paragraph 11A -Chapter 1 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 29, 30 -Article 5 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Accounting Principles Board Opinion (APB) -Number 12 -Paragraph 10 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Article 3 Reference 5: 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 + Details
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