Debt - Senior Unsecured Credit Facility and Unsecured Term Loans (Details)		3 Months Ended		6 Months Ended		9 Months Ended	10 Months Ended	19 Months Ended
	Jun. 09, 2020	Jun. 30, 2020 USD ($)	Jun. 30, 2019 USD ($)	Jun. 30, 2020 USD ($)	Jun. 30, 2019 USD ($)	Jan. 01, 2022	Mar. 31, 2021 USD ($)	Jan. 01, 2022	Apr. 01, 2021	Dec. 31, 2019 USD ($)
Line of Credit Facility [Line Items]
Percent of unused portion line of credit facility triggering lower commitment fee (as a percent)				50.00%
Senior unsecured credit facility		$ 148,985,000		$ 148,985,000						$ 75,000,000
Unsecured Term Loans
Line of Credit Facility [Line Items]
Interest incurred on the facility		2,900,000	$ 3,500,000	$ 6,100,000	$ 6,900,000
Minimum
Line of Credit Facility [Line Items]
Line of credit facility, unused capacity, commitment fee (as a percent)				0.20%
Maximum
Line of Credit Facility [Line Items]
Line of credit facility, unused capacity, commitment fee (as a percent)				0.30%
Less than 30% | Maximum
Line of Credit Facility [Line Items]
Ratio of net indebtedness to EBITDA				0.30
Less than 30% | LIBOR | Revolving Credit Facility
Line of Credit Facility [Line Items]
Basis spread on variable rate				1.40%
Less than 30% | LIBOR | Unsecured Term Loans
Line of Credit Facility [Line Items]
Basis spread on variable rate				1.35%
Greater than or equal to 30% but less than 35% | Minimum
Line of Credit Facility [Line Items]
Ratio of net indebtedness to EBITDA				0.30
Greater than or equal to 30% but less than 35% | Maximum
Line of Credit Facility [Line Items]
Ratio of net indebtedness to EBITDA				0.35
Greater than or equal to 30% but less than 35% | LIBOR | Revolving Credit Facility
Line of Credit Facility [Line Items]
Basis spread on variable rate				1.45%
Greater than or equal to 30% but less than 35% | LIBOR | Unsecured Term Loans
Line of Credit Facility [Line Items]
Basis spread on variable rate				1.40%
Greater than or equal to 35% but less than 40% | Minimum
Line of Credit Facility [Line Items]
Ratio of net indebtedness to EBITDA				0.35
Greater than or equal to 35% but less than 40% | Maximum
Line of Credit Facility [Line Items]
Ratio of net indebtedness to EBITDA				0.40
Greater than or equal to 35% but less than 40% | LIBOR | Revolving Credit Facility
Line of Credit Facility [Line Items]
Basis spread on variable rate				1.50%
Greater than or equal to 35% but less than 40% | LIBOR | Unsecured Term Loans
Line of Credit Facility [Line Items]
Basis spread on variable rate				1.45%
Greater than or equal to 40% but less than 45% | Minimum
Line of Credit Facility [Line Items]
Ratio of net indebtedness to EBITDA				0.40
Greater than or equal to 40% but less than 45% | Maximum
Line of Credit Facility [Line Items]
Ratio of net indebtedness to EBITDA				0.45
Greater than or equal to 40% but less than 45% | LIBOR | Revolving Credit Facility
Line of Credit Facility [Line Items]
Basis spread on variable rate				1.55%
Greater than or equal to 40% but less than 45% | LIBOR | Unsecured Term Loans
Line of Credit Facility [Line Items]
Basis spread on variable rate				1.50%
Greater than or equal to 45% but less than 50% | Minimum
Line of Credit Facility [Line Items]
Ratio of net indebtedness to EBITDA				0.45
Greater than or equal to 45% but less than 50% | Maximum
Line of Credit Facility [Line Items]
Ratio of net indebtedness to EBITDA				0.50
Greater than or equal to 45% but less than 50% | LIBOR | Revolving Credit Facility
Line of Credit Facility [Line Items]
Basis spread on variable rate				1.70%
Greater than or equal to 45% but less than 50% | LIBOR | Unsecured Term Loans
Line of Credit Facility [Line Items]
Basis spread on variable rate				1.65%
Greater than or equal to 50% but less than 55% | Minimum
Line of Credit Facility [Line Items]
Ratio of net indebtedness to EBITDA				0.50
Greater than or equal to 50% but less than 55% | Maximum
Line of Credit Facility [Line Items]
Ratio of net indebtedness to EBITDA				0.55
Greater than or equal to 50% but less than 55% | LIBOR | Revolving Credit Facility
Line of Credit Facility [Line Items]
Basis spread on variable rate				1.90%
Greater than or equal to 50% but less than 55% | LIBOR | Unsecured Term Loans
Line of Credit Facility [Line Items]
Basis spread on variable rate				1.85%
Greater than or equal to 55% | Minimum
Line of Credit Facility [Line Items]
Ratio of net indebtedness to EBITDA				0.55
Greater than or equal to 55% | LIBOR | Revolving Credit Facility
Line of Credit Facility [Line Items]
Basis spread on variable rate				2.05%
Greater than or equal to 55% | LIBOR | Unsecured Term Loans
Line of Credit Facility [Line Items]
Basis spread on variable rate				2.00%
Revolving Credit Facility | Revolving Credit Facility
Line of Credit Facility [Line Items]
Maximum borrowing capacity		400,000,000		$ 400,000,000
Senior unsecured credit facility		148,985,000		148,985,000						75,000,000
Interest and unused credit facility fees		1,800,000	$ 1,000,000.0	$ 2,500,000	$ 1,700,000
Revolving Credit Facility | LIBOR | Revolving Credit Facility
Line of Credit Facility [Line Items]
Basis spread on variable rate				2.40%
Revolving Credit Facility | LIBOR | Minimum | Revolving Credit Facility
Line of Credit Facility [Line Items]
Basis spread on variable rate	0.25%
Unsecured Term Loan due July 2024 | Unsecured Term Loans
Line of Credit Facility [Line Items]
Principal balance		350,000,000		$ 350,000,000						350,000,000
Unsecured Term Loan due July 2024 | LIBOR | Unsecured Term Loans
Line of Credit Facility [Line Items]
Basis spread on variable rate				2.35%
Unsecured Term Loan Due October 2023 | Unsecured Term Loans
Line of Credit Facility [Line Items]
Principal balance		$ 50,000,000		$ 50,000,000						$ 50,000,000
Unsecured Term Loan Due October 2023 | LIBOR | Unsecured Term Loans
Line of Credit Facility [Line Items]
Basis spread on variable rate				2.35%
Forecast
Line of Credit Facility [Line Items]
Minimum liquidity covenant							$ 100,000,000.0
Covenant, acquisition limitation							$ 300,000,000
Maximum leverage ratio (as a percent)							0.60		0.65
Unencumbered leverage ratio							60.00%		65.00%
Forecast | Revolving Credit Facility | LIBOR | Revolving Credit Facility
Line of Credit Facility [Line Items]
Basis spread on variable rate								2.40%
Forecast | Unsecured Term Loan Due October 2023 | LIBOR | Unsecured Term Loans
Line of Credit Facility [Line Items]
Basis spread on variable rate								2.35%
Testing Period One | Forecast | Minimum
Line of Credit Facility [Line Items]
Unencumbered implied debt service coverage ratio						1.00
Testing Period Two | Forecast | Minimum
Line of Credit Facility [Line Items]
Unencumbered implied debt service coverage ratio						1.00
Testing Period Three | Forecast | Minimum
Line of Credit Facility [Line Items]
Unencumbered implied debt service coverage ratio						1.10
Testing Periods Thereafter | Forecast | Minimum
Line of Credit Facility [Line Items]
Unencumbered implied debt service coverage ratio						1.20