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Related-Party Transactions - Additional Information (Detail) |  | 1 Months Ended | 3 Months Ended |
--- | --- | --- | --- | ---
Jul. 01, 2015 quarter | Jul. 31, 2015 | Mar. 31, 2017 USD ($) officer | Mar. 31, 2016 USD ($) | Dec. 31, 2016 USD ($)
Related Party Transaction [Line Items] |  |  |  |  |  |
Number of executive officers | officer |  |  |  | 2 |  |
Due to Adviser and Administrator | [1] |  |  | $ 2,103,000 |  | $ 2,075,000
Annual base management fee, in percentage of stockholders' equity, adjusted to unrealized gains or losses (as percent) |  | 1.50% |  |  |  |
Quarterly base management fee, in percentage of stockholders' equity, adjusted to unrealized gains or losses (as percent) |  | 0.375% |  |  |  |
Annual base management fee, in percentage of stockholders' equity, in excess of recorded value of preferred stock (as percent) |  | 2.00% |  |  |  |
Base management fee | [2] |  |  | $ 1,181,000 | $ 861,000 |
Pre-incentive quarterly fee FFO in percentage of common stockholders' equity that will reward the Adviser (as percent) |  | 2.00% |  | 1.75% |  |
Pre-incentive annual fee FFO in percentage of common stockholders' equity that will reward the Adviser (as percent) |  | 8.00% |  | 7.00% |  |
Amount to be paid to Adviser in percentage of pre-incentive fee condition one (as percent) |  | 15.00% |  | 100.00% |  |
Number of quarters used for the cap of average quarterly incentive fees | quarter |  | 4 |  |  |  |
Pre-incentive fee in percentage of common stockholders' equity that awards Adviser hundred percent of amount of pre-incentive fee, maximum percentage |  |  |  | 2.1875% |  |
Amount to be paid to Adviser in percentage of pre-incentive fee condition two (as percent) |  |  |  | 20.00% |  |
Pre-incentive fee in percentage of common stockholders' equity that awards the Adviser 20% of the amount of the pre-incentive fee, minimum percentage (as percent) |  |  |  | 2.1875% |  |
Incentive fee | [2] |  |  | $ 569,000 | 618,000 |
Capital gains-based incentive fee (as percent) |  | 15.00% |  |  |  |
Capital gain fee |  |  |  | $ 0 | 0 |
Notice period for termination of agreement without cause |  | 120 days |  |  |  |
Percentage of independent directors to terminate the Amended Advisory Agreement (as percent) |  |  |  | 66670.00% |  |
Termination fee payable (as percent) |  |  | 200.00% |  |  |
Notice period for termination of agreement with cause |  | 30 days |  |  |  |
Administration fee | [2] |  |  | $ 360,000 | 404,000 |
Fees paid |  |  |  | $ 0 | $ 80,000 |
Financing fee on total secured mortgages percentage (as percent) |  |  |  |  | 0.43% |
Minimum |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |
Percentage of the amount of the mortgage (as percent) |  |  |  | 0.15% |  |
Maximum |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |
Percentage of the amount of the mortgage (as percent) |  |  |  | 1.00% |  |
[1] | Refer to Note 2 "Related-Party Transactions"
[2] | Refer to Note 2 “Related-Party Transactions”

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