Basis of Presentation and Summary of Significant Accounting Policies (Details) ft² in Millions	Oct. 01, 2015 ft² property state	Sep. 30, 2015 state
Entity Information [Line Items]
Number of states in which office properties are located | state		6
Percentage of noncontrolling interest in operating partnerships		4.10%
Subsequent Event
Entity Information [Line Items]
Number of office and parking properties | property	38
Number of states in which office properties are located | state	6
Net rentable area (sqft)	14.9
Subsidiaries | Subsequent Event
Entity Information [Line Items]
Net rentable area (sqft)	4.2
Parkway Properties LP
Entity Information [Line Items]
Company's ownership (as a percent)		95.90%