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Mandatorily Redeemable Preferred Stock - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands | 1 Months Ended | 3 Months Ended | 9 Months Ended |
--- | --- | --- | --- | ---
Feb. 29, 2012 | Sep. 30, 2016 | Sep. 30, 2016 | Dec. 31, 2015
Class of Stock [Line Items] |  |  |  |
Write-off of deferred offering costs |  | $ 60 | $ 200 |
Mandatorily Redeemable Preferred Stock [Member] |  |  |  |
Class of Stock [Line Items] |  |  |  |
Redeemable preferred stock, shares issued (in shares) | 1,540,000 |  |  |
Redeemable preferred stock, par value (in dollars per share) | $ 0.001 |  |  |
Public offering price | $ 25.00 |  |  |
Gross proceeds of the offering | $ 38,500 |  |  |
Net proceeds, after deducting offering expenses | $ 36,700 |  |  |
Series C Preferred Stock [Member] |  |  |  |
Class of Stock [Line Items] |  |  |  |
Redeemable preferred stock, dividend rate percentage | 7.125% |  |  |
Series C Preferred Stock [Member] | Mandatorily Redeemable Preferred Stock [Member] |  |  |  |
Class of Stock [Line Items] |  |  |  |
Redeemable preferred stock, shares issued (in shares) |  | 0 | 0 | 1,540,000
Redeemable preferred stock, par value (in dollars per share) |  | $ 0.001 | $ 0.001 | $ 0.001

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- Definition Net proceeds after deducting offering expenses. + References No definition available. + Details
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- Definition Preferred Stock, Write Off Of Offering Costs + References No definition available. + Details
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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 The percentage rate used to calculate dividend payments on preferred stock. + References No definition available. + Details
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- Definition Face amount or stated value per share of preferred stock nonredeemable or redeemable solely at the option of the issuer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.28) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 29 -Article 5 + Details
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- Definition Total number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) issued to shareholders (includes related preferred shares that were issued, repurchased, and remain in the treasury). May be all or portion of the number of preferred shares authorized. Excludes preferred shares that are classified as debt. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.28) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 29 -Article 5 + Details
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- Definition Proceeds from issuance of capital stock which provides for a specific dividend that is paid to the shareholders before any dividends to common stockholders and which takes precedence over common stockholders in the event of liquidation. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 14 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3255-108585 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Financing Activities -URI http://asc.fasb.org/extlink&oid=6513228 + Details
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