Net Income (Loss) Per Common Share Reconciling the Components of Basic and Diluted Net Income (Loss) per Common Share (Details) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Net income attributable to common shareholders	$ 71,823	$ 226,566	$ 131,099	$ 342,170
Less: dividends on participating securities	(352)	(350)	(1,064)	(1,125)
Basic net income attributable to common shareholders	71,471	226,216	130,035	341,045
Add back dividends on dilutive participating securities	0	350	0	1,125
Noncontrolling interest in earnings of common unitholders	638	1,968	1,164	2,971
Diluted net income attributable to common shareholders	$ 72,109	$ 228,534	$ 131,199	$ 345,141
Weighted average number of common shares/units outstanding, Basic	371,082	362,416	369,375	360,424
Weighted average Limited Partner Units outstanding	3,330	3,142	3,296	3,118
Other potential dilutive shares/units	422	1,713	420	1,801
Weighted average number of common shares/units and potential dilutive securities	374,834	367,271	373,091	365,343
Duke Realty Limited Partnership [Member]
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Net income attributable to common shareholders	$ 72,461	$ 228,534	$ 132,263	$ 345,141
Less: dividends on participating securities	(352)	(350)	(1,064)	(1,125)
Basic net income attributable to common unitholders	72,109	228,184	131,199	344,016
Add back dividends on dilutive participating securities	0	350	0	1,125
Diluted net income attributable to common unitholders	$ 72,109	$ 228,534	$ 131,199	$ 345,141
Weighted average number of common shares/units outstanding, Basic	374,412	365,558	372,671	363,542
Other potential dilutive shares/units	422	1,713	420	1,801
Weighted average number of common shares/units and potential dilutive securities	374,834	367,271	373,091	365,343