v3.8.0.1

Acquisitions - Acquisitions Closed (Parenthetical) - (Detail) - USD ($) $ in Thousands | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Business Acquisition [Line Items] |  |  |
Mortgages assumed | $ 11,926 | $ 0 | $ 0
ASU 2017-01 |  |  |
Business Acquisition [Line Items] |  |  |
Acquisition costs capitalized | 12,349 |  |
Healthcare |  |  |
Business Acquisition [Line Items] |  |  |
Mortgages assumed | $ 5,205 |  |
Interest rate | 1-month LIBOR plus 3.0% |  |
Mortgage, Maturity date | Aug. 31, 2021 |  |
Healthcare | LIBOR |  |  |
Business Acquisition [Line Items] |  |  |
Mortgage, Interest rate | 3.00% |  |
Healthcare | Interest Rate Swap |  |  |
Business Acquisition [Line Items] |  |  |
Derivative, Fixed rate | 1.02% |  |
Derivative, Maturity date | Aug. 31, 2021 |  |
Other |  |  |
Business Acquisition [Line Items] |  |  |
Mortgages assumed | $ 6,721 |  |
Mortgage, Interest rate | 3.65% |  |
Mortgage, Maturity date | Oct. 31, 2026 |  |

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