Commitments and Contingencies Commitments and Contingencies - Guarantees (Details) - Financial Guarantee - USD ($) $ in Thousands	Jun. 30, 2019	Jan. 08, 2019
Commitments and Contingencies
Guarantor obligations, maximum exposure (up to)	$ 56,734
The Residences at Annapolis Junction
Commitments and Contingencies
Guarantor obligations, maximum exposure (up to)	8,300
Delray Plaza
Commitments and Contingencies
Guarantor obligations, maximum exposure (up to)	5,180	$ 5,200
Nexton Square
Commitments and Contingencies
Guarantor obligations, maximum exposure (up to)	12,600
Interlock Commercial
Commitments and Contingencies
Guarantor obligations, maximum exposure (up to)	$ 30,654