Financial Instruments and Fair Value Measurements - Liabilities Measured at FV (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020	Jun. 30, 2019	Jan. 31, 2019
Interest rate swap | Watercrest JV
Financial instruments and fair value measurements
Notional amount			$ 20,000
Recurring basis
Financial instruments and fair value measurements
Liabilities	$ 1,625	$ 1,993
Recurring basis | Interest rate swap | Other liabilities.
Financial instruments and fair value measurements
Derivative liabilities	1,015	1,172
Recurring basis | Interest rate swap | Investment in unconsolidated joint ventures
Financial instruments and fair value measurements
Derivative liabilities	610	821
Recurring basis | Level 2
Financial instruments and fair value measurements
Liabilities	1,625	1,993
Recurring basis | Level 2 | Interest rate swap | Pier Park TPS JV
Financial instruments and fair value measurements
Derivative liabilities	600	800
Recurring basis | Level 2 | Interest rate swap | Other liabilities.
Financial instruments and fair value measurements
Derivative liabilities	1,015	1,172
Recurring basis | Level 2 | Interest rate swap | Investment in unconsolidated joint ventures
Financial instruments and fair value measurements
Derivative liabilities	$ 610	$ 821
Pier Park TPS JV | Interest rate swap
Financial instruments and fair value measurements
Notional amount				$ 14,400