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Restricted Shares Issued in Conjunction with Stock Plan (Detail) - Restricted Stock $ in Millions | 12 Months Ended
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Dec. 31, 2016 USD ($) shares
Period 1 |
Class of Stock [Line Items] |
Issuance Date | Jan. 31, 2014
Shares | shares | 35,500
Aggregate Market Value | $ | $ 1.1
Period 2 |
Class of Stock [Line Items] |
Issuance Date | Jan. 26, 2015
Shares | shares | 40,010
Aggregate Market Value | $ | $ 1.5
Period 3 |
Class of Stock [Line Items] |
Issuance Date | Jan. 26, 2016
Shares | shares | 43,220
Aggregate Market Value | $ | $ 1.6
Period 4 |
Class of Stock [Line Items] |
Issuance Date | Apr. 19, 2016
Shares | shares | 800
Period 4 | Maximum |
Class of Stock [Line Items] |
Aggregate Market Value | $ | $ 0.1

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- Definition The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). + 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 (c)(2)(iii)(1) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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