Rental Property - Summary (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Property Subject to or Available for Operating Lease [Line Items]
Rental property, net	$ 4,050,955	$ 3,998,507
Deferred leasing intangible assets, accumulated amortization	264,262	241,304
Land
Property Subject to or Available for Operating Lease [Line Items]
Rental property, net	447,356	435,923
Buildings, net of accumulated depreciation of $311,326 and $254,458, respectively
Property Subject to or Available for Operating Lease [Line Items]
Rental property, net	2,862,026	2,787,234
Rental property, accumulated depreciation	311,326	254,458
Tenant improvements, net of accumulated depreciation of $23,641 and $21,487, respectively
Property Subject to or Available for Operating Lease [Line Items]
Rental property, net	39,495	38,339
Rental property, accumulated depreciation	23,641	21,487
Building and land improvements, net of accumulated depreciation of $138,402 and $111,688, respectively
Property Subject to or Available for Operating Lease [Line Items]
Rental property, net	243,807	232,456
Rental property, accumulated depreciation	138,402	111,688
Construction in progress
Property Subject to or Available for Operating Lease [Line Items]
Rental property, net	19,225	29,406
Deferred leasing intangibles, net of accumulated amortization of $264,262 and $241,304, respectively
Property Subject to or Available for Operating Lease [Line Items]
Rental property, net	$ 439,046	$ 475,149