(Common Units) (Narrative) (Details) $ / shares in Units, $ in Millions		6 Months Ended
	Feb. 06, 2020 USD ($) shares	Jun. 30, 2020 USD ($) yr $ / shares shares
MYLTIP 2017 [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Final awards percentage of target	83.80%
Value of MYLTIP Awards | $	$ 17.6
MYLTIP Units forfeited	270,942
OP Units [Member]
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
OP Units for redemption (in shares)		764,640
Redemption of OP units issued on conversion of LTIP, OPP and MYLTIP units (in shares)		82,551
MYLTIP Units distribution as percentage of OP Unit distribution prior to measurement date		10.00%
Restriction on redemption of OP Unit to Common Stock (in years) | yr		1
Redemption of OP Unit equivalent to Common Stock (in shares)		1
Common units of operating partnership if converted value | $		$ 1,600.0
Closing price of common stock (in dollars per share) | $ / shares		$ 90.38