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Long Term Restricted Stock Units (Details) - Plan - RSUs | 1 Months Ended | 12 Months Ended
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Dec. 31, 2009 item | Dec. 31, 2017 shares
Long-Term Restricted Stock Units |  |
Minimum number of non-employee members of the Board needed to authorize restricted stock units | item | 2 |
Number of options granted (in shares) |  | 0
Outstanding grants (in shares) |  | 0

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- Definition The minimum number of non-employee members of the Board authorized to issue restricted stock units. The members are appointed by the Board each of whom is both a non-employee director and an outside director. + References No definition available. + Details
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Balance Type: | na
Period Type: | duration

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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition Gross number of share options (or share units) granted during the period. + References No definition available. + Details
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Period Type: | duration

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- Definition Number of options outstanding, including both vested and non-vested options. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1)(i)-(ii) -URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901 + Details
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Balance Type: | na
Period Type: | instant

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- Details
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- Details
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Balance Type: |
Period Type: |