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Equity and Mezzanine Equity - Additional Information (Detail) |  |  |  |  | 12 Months Ended |  |  |  |  |  |  |  |
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Oct. 28, 2019 USD ($) $ / shares shares | Oct. 04, 2019 USD ($) $ / shares shares | Oct. 30, 2018 USD ($) ft² property shares | Apr. 11, 2018 shares | Dec. 31, 2019 USD ($) shares | Dec. 31, 2018 USD ($) shares | Dec. 03, 2019 USD ($) | Dec. 02, 2019 shares | Sep. 30, 2019 USD ($) | Sep. 27, 2019 shares | Sep. 26, 2019 shares | Jan. 11, 2019 USD ($) | Dec. 31, 2016 USD ($) | Feb. 29, 2016 USD ($)
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Authorized but unissued shares reclassified from senior common stock to common stock |  |  |  | 3,500,000 |  |  |  |  |  |  |  |  |  |
Senior common stock, authorized shares unissued (in shares) |  |  |  | 57,969 |  |  |  |  |  |  |  |  |  |
Capital stock, shares authorized |  |  |  | 100,000,000 |  |  |  |  |  |  |  |  |  |
Common stock, shares authorized (in shares) |  |  |  | 87,700,000 | 86,290,000 | 87,700,000 |  | 86,290,000 |  | 83,700,000 | 87,700,000 |  |  |
Common stock, shares authorized but unissued (in shares) |  |  |  |  |  |  |  | 2,590,000 |  |  |  |  |  |
Aggregate Purchase Price | $ |  |  |  |  | $ 130,313,000 | $ 63,245,000 |  |  |  |  |  |  |  |
Units held by noncontrolling owners (in shares) |  |  |  |  | 479,637 | 742,937 |  |  |  |  |  |  |  |
Series A Cumulative Redeemable Preferred Stock |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Preferred stock, shares authorized but unissued (in shares) |  |  |  |  |  |  |  | 2,600,000 |  |  |  |  |  |
Series B Cumulative Redeemable Preferred Stock |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Preferred stock, shares authorized but unissued (in shares) |  |  |  |  |  |  |  | 2,750,000 |  |  |  |  |  |
Series D Cumulative Redeemable Preferred Stock |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Minimum vote need to trigger change in control from tender offer (as percent) |  |  |  |  | 90.00% |  |  |  |  |  |  |  |  |
Redeemable preferred stock, shares authorized (in shares) |  |  |  |  |  |  |  | 6,000,000 |  |  |  |  |  |
Senior Common Stock |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock, shares authorized (in shares) |  |  |  |  |  |  |  | 950,000 |  |  |  |  |  |
Series E Cumulative Redeemable Preferred Stock |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Redeemable preferred stock, shares issued (in shares) |  | 2,760,000 |  |  |  |  |  |  |  |  |  |  |  |
Public offering price (in dollars per share) | $ / shares |  | $ 25.00 |  |  |  |  |  |  |  |  |  |  |  |
Gross proceeds of the offering | $ |  | $ 69,000,000 |  |  |  |  |  |  |  |  |  |  |  |
Net proceeds, after deducting offering expenses | $ |  | $ 66,600,000 |  |  |  |  |  |  |  |  |  |  |  |
Preferred stock, shares authorized but unissued (in shares) |  |  |  |  |  |  |  | 10,000 |  |  |  |  |  |
Redeemable preferred stock, shares authorized (in shares) |  |  |  |  |  |  |  | 6,760,000 |  | 4,000,000 |  |  |  |
Series A and B Preferred Stock |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Redeemable preferred stock, shares issued (in shares) |  |  |  |  | 0 | 2,264,000 |  |  |  |  |  |  |  |
Redeemable preferred stock, shares authorized (in shares) |  |  |  |  | 0 | 5,350,000 |  |  |  |  |  |  |  |
Preferred Stock | Series A Cumulative Redeemable Preferred Stock |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Treasury stock, shares, acquired | 1,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |
Preferred stock, redemption price per share (in usd per share) | $ / shares | $ 25.1506944 |  |  |  |  |  |  |  |  |  |  |  |  |
Preferred Stock | Series B Cumulative Redeemable Preferred Stock |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Treasury stock, shares, acquired | 1,264,000 |  |  |  |  |  |  |  |  |  |  |  |  |
Preferred stock, redemption price per share (in usd per share) | $ / shares | $ 25.1458333 |  |  |  |  |  |  |  |  |  |  |  |  |
Preferred Stock | Series D Cumulative Redeemable Preferred Stock |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Preferred stock, dividend rate (as percent) |  |  |  |  | 7.00% |  |  |  |  |  |  |  |  |
Preferred Stock | Series E Cumulative Redeemable Preferred Stock |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Preferred stock, dividend rate (as percent) |  |  |  |  | 6.625% |  |  |  |  |  |  |  |  |
Preferred Stock | Series A and B Preferred Stock |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net proceeds from sale of shares | $ | $ 2,700,000 |  |  |  |  |  |  |  |  |  |  |  |  |
Preferred stock, redemption price | $ | $ 56,900,000 |  |  |  |  |  |  |  |  |  |  |  |  |
2019 Universal Shelf |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Universal registration statement, amount authorized | $ |  |  |  |  |  |  |  |  | $ 438,000,000 |  |  | $ 500,000,000 |  |
Cantor Fitzgerald & Co | Preferred Stock | Series B Cumulative Redeemable Preferred Stock |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Maximum aggregate sales price of shares to be issued under open market sale agreement | $ |  |  |  |  |  |  |  |  | $ 40,000,000.0 |  |  |  |  |
Preferred stock, dividend rate (as percent) |  |  |  |  | 7.50% |  |  |  |  |  |  |  |  |
Cantor Fitzgerald & Co | Preferred Stock | Series D Cumulative Redeemable Preferred Stock |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Maximum aggregate sales price of shares to be issued under open market sale agreement | $ |  |  |  |  |  |  |  |  |  |  |  |  | $ 50,000,000.0 |
Cantor Fitzgerald & Co | Preferred Stock | Series E Cumulative Redeemable Preferred Stock |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Maximum aggregate sales price of shares to be issued under open market sale agreement | $ |  |  |  |  |  |  | $ 100,000,000.0 |  |  |  |  |  |  |
Cantor Fitzgerald & Co | Common Stock ATM Program | Common Stock and Non-controlling OP Units |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Maximum aggregate sales price of shares to be issued under open market sale agreement | $ |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 250,000,000
Number of shares sold (in shares) |  |  |  |  | 3,000,000 |  |  |  |  |  |  |  |  |
Net proceeds from sale of shares | $ |  |  |  |  | $ 64,500,000 |  |  |  |  |  |  |  |  |
Open market dale agreement, value of remaining capacity | $ |  |  |  |  | $ 237,500,000 |  |  |  |  |  |  |  |  |
Cantor Fitzgerald & Co | Series A and B Preferred Stock ATM Programs | Preferred Stock | Series A Cumulative Redeemable Preferred Stock |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Preferred stock, dividend rate (as percent) |  |  |  |  | 7.75% |  |  |  |  |  |  |  |  |
Operating Partnership |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Company ownership percentage of voting securities |  |  |  |  | 98.60% | 97.50% |  |  |  |  |  |  |  |
Number of units issued in acquisition (in shares) |  |  | 742,937 |  |  |  |  |  |  |  |  |  |  |
Number of units redeemed in acquisition (in shares) |  |  | 263,300 |  |  |  |  |  |  |  |  |  |  |
Detroit, Michigan |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class of Stock [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of units issued in acquisition (in shares) |  |  | 742,937 |  |  |  |  |  |  |  |  |  |  |
Aggregate Square Footage | ft² |  |  | 218,703 |  |  |  |  |  |  |  |  |  |  |
Aggregate Purchase Price | $ |  |  | $ 21,700,000 |  |  |  |  |  |  |  |  |  |  |
Number of properties in portfolio | property |  |  | 2 |  |  |  |  |  |  |  |  |  |  |

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