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v3.8.0.1

Subsequent Events - Additional Information (Details) - USD ($) |  |  |  | 1 Months Ended |
--- | --- | --- | --- | --- | ---
Oct. 27, 2017 | Oct. 19, 2017 | Oct. 05, 2015 | Oct. 31, 2017 | Aug. 31, 2013
Subsequent Event [Line Items] |  |  |  |  |
Maximum borrowing capacity |  |  | $ 150,000,000.0 |  | $ 100,000,000.0
Extension fee on initial maturity (as percent) |  |  | 0.25% |  |
Term Loan Facility |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |
Extension fee on initial maturity (as percent) |  |  | 0.05% |  |
Line of credit |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |
Maximum borrowing capacity |  |  | $ 85,000,000.0 |  |
Line of credit | Term Loan Facility |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |
Maximum borrowing capacity |  |  | $ 25,000,000.0 |  |
Subsequent event | Common Stock ATM Program |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |
Consideration received |  |  |  | $ 200,000 |
Number of shares issued (in shares) |  |  |  | 10,000 |
Subsequent event | Series, A, B and D Preferred ATM Programs |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |
Number of shares issued (in shares) |  |  |  | 0 |
Subsequent event | Line of credit |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |
Term of debt | 4 years |  |  |  |
Fees incurred | $ 900,000 |  |  |  |
Subsequent event | Line of credit | Term Loan Facility |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |
Maximum borrowing capacity | $ 75,000,000.0 |  |  |  |
Term of debt | 5 years |  |  |  |
Subsequent event | Line of credit | Term Loan Facility | LIBOR |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |
Basis spread (as percent) | 2.75% |  |  |  |
Subsequent event | Arlington, Texas |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |
Renewal term |  | 10 years |  |  |
Subsequent event | Arlington, Texas | Disposed of by sale | Plan |  |  |  |  |
Subsequent Event [Line Items] |  |  |  |  |
Consideration received |  | $ 5,600,000 |  |  |

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- Definition Amount of the fee that accompanies borrowing money under the debt instrument. + 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 210.5-02.22(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Term of lessee's operating lease renewal, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918673-209980 + Details
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