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Mandatorily Redeemable Term Preferred Stock - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions | 1 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Feb. 29, 2012 | Dec. 31, 2016 | Dec. 31, 2015
Class of Stock [Line Items] |  |  |
Preferred Stock mandatory redemption date | Jan. 31, 2017 |  |
\Write -off of unamortized offering costs |  | $ 0.2 |
Series C Preferred Stock [Member] |  |  |
Class of Stock [Line Items] |  |  |
Redeemable preferred stock, dividend rate percentage (as percent) | 7.125% |  |
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 (in dollars per share) | $ 25.00 |  |
Gross proceeds of the offering | $ 38.5 |  |
Net proceeds, after deducting offering expenses | $ 36.7 |  |
Mandatorily Redeemable Preferred Stock [Member] | Series C Preferred Stock [Member] |  |  |
Class of Stock [Line Items] |  |  |
Redeemable preferred stock, shares issued (in shares) |  | 0 | 1,540,000
Redeemable preferred stock, par value (in dollars per share) |  | $ 0.001 | $ 0.001

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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 Date the preferred stock has been redeemed, in CCYY-MM-DD format. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21564-112644 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21475-112644 + 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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