Leases	9 Months Ended
	Sep. 30, 2020
Leases [Abstract]
Leases	Leases We generally lease our office properties to lessees in exchange for fixed monthly payments that cover rent, property taxes, insurance and certain cost recoveries, primarily common area maintenance. Office properties owned by us that are under lease are primarily located in Atlanta, Charlotte, Nashville, Orlando, Pittsburgh, Raleigh, Richmond and Tampa and are leased to a wide variety of lessees across many industries. Our leases are operating leases and mostly range from three to 10 years. We recognized rental and other revenues related to operating lease payments of $178.9 million and $184.2 million during the three months ended September 30, 2020 and 2019, respectively, and $549.5 million and $534.2 million during the nine months ended September 30, 2020 and 2019, respectively. Included in these amounts are variable lease payments of $12.8 million and $17.3 million during the three months ended September 30, 2020 and 2019, respectively, and $42.7 million and $49.2 million during the nine months ended September 30, 2020 and 2019, respectively.