COPT Defense Properties Annual report pursuant to Section 13 and 15(d)

Information by Business Segment (Details)

Information by Business Segment (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Segment financial information for real estate operations
Revenues from real estate operations	$ 525,964	$ 519,068	$ 479,711
Property operating expenses	(197,530)	(194,488)	(179,799)
UJV NOI allocable to COPT	2,305	0	0
NOI from real estate operations	330,739	324,580	299,912
Additions to long-lived assets	70,324	335,269	64,601
Transfers from non-operating properties	184,640	307,120	141,899
Segment assets	3,780,885	3,909,312
Defense/Information Technology Sector [Member]
Segment financial information for real estate operations
Revenues from real estate operations	406,210	394,283	376,742
Property operating expenses	(148,705)	(144,444)	(137,486)
UJV NOI allocable to COPT	2,305
NOI from real estate operations	259,810	249,839	239,256
Additions to long-lived assets	57,131	130,670	45,379
Transfers from non-operating properties	184,943	194,647	121,227
Segment assets	2,308,189	2,342,746	2,188,021
Defense/Information Technology Sector [Member] \| Fort Meade/BW Corridor [Member]
Segment financial information for real estate operations
Revenues from real estate operations	245,354	244,274	233,764
Property operating expenses	(83,684)	(83,309)	(80,824)
UJV NOI allocable to COPT	0
NOI from real estate operations	161,670	160,965	152,940
Additions to long-lived assets	26,267	31,883	24,173
Transfers from non-operating properties	49,937	45,560	56,699
Segment assets	1,255,230	1,290,028	1,264,353
Defense/Information Technology Sector [Member] \| Northern Virginia Defense/IT [Member]
Segment financial information for real estate operations
Revenues from real estate operations	48,964	49,199	48,313
Property operating expenses	(17,824)	(20,107)	(19,071)
UJV NOI allocable to COPT	0
NOI from real estate operations	31,140	29,092	29,242
Additions to long-lived assets	17,344	90,248	7,119
Transfers from non-operating properties	28,230	50,690	360
Segment assets	404,438	411,196	372,041
Defense/Information Technology Sector [Member] \| Lackland Air Force Base [Member]
Segment financial information for real estate operations
Revenues from real estate operations	46,803	39,659	34,463
Property operating expenses	(27,357)	(22,004)	(19,677)
UJV NOI allocable to COPT	0
NOI from real estate operations	19,446	17,655	14,786
Additions to long-lived assets	0	0	0
Transfers from non-operating properties	240	32,307	0
Segment assets	131,957	134,381	102,232
Defense/Information Technology Sector [Member] \| Navy Support Locations [Member]
Segment financial information for real estate operations
Revenues from real estate operations	28,197	28,177	31,335
Property operating expenses	(12,690)	(13,229)	(12,576)
UJV NOI allocable to COPT	0
NOI from real estate operations	15,507	14,948	18,759
Additions to long-lived assets	9,168	7,656	10,010
Transfers from non-operating properties	0	1,408	0
Segment assets	196,486	196,090	195,972
Defense/Information Technology Sector [Member] \| Redstone Arsenal [Member]
Segment financial information for real estate operations
Revenues from real estate operations	13,056	11,228	10,446
Property operating expenses	(4,476)	(3,497)	(3,066)
UJV NOI allocable to COPT	0
NOI from real estate operations	8,580	7,731	7,380
Additions to long-lived assets	4,352	883	4,077
Transfers from non-operating properties	3,169	13,190	21,014
Segment assets	110,395	108,038	97,209
Defense/Information Technology Sector [Member] \| Data Center Shells [Member]
Segment financial information for real estate operations
Revenues from real estate operations	23,836	21,746	18,421
Property operating expenses	(2,674)	(2,298)	(2,272)
UJV NOI allocable to COPT	2,305
NOI from real estate operations	23,467	19,448	16,149
Additions to long-lived assets	0	0	0
Transfers from non-operating properties	103,367	51,492	43,154
Segment assets	209,683	203,013	156,214
Regional Office [Member]
Segment financial information for real estate operations
Revenues from real estate operations	85,805	98,165	85,025
Property operating expenses	(34,095)	(36,165)	(31,427)
UJV NOI allocable to COPT	0
NOI from real estate operations	51,710	62,000	53,598
Additions to long-lived assets	12,559	204,139	19,290
Transfers from non-operating properties	82	22,313	17,942
Segment assets	442,811	608,471	526,988
Operating wholesale data centers [Member]
Segment financial information for real estate operations
Revenues from real estate operations	26,869	19,032	10,430
Property operating expenses	(11,512)	(10,402)	(7,286)
UJV NOI allocable to COPT	0
NOI from real estate operations	15,357	8,630	3,144
Additions to long-lived assets	299	132	22
Transfers from non-operating properties	(377)	89,745	1,108
Segment assets	231,954	243,338	163,177
Other [Member]
Segment financial information for real estate operations
Revenues from real estate operations	7,080	7,588	7,514
Property operating expenses	(3,218)	(3,477)	(3,600)
UJV NOI allocable to COPT	0
NOI from real estate operations	3,862	4,111	3,914
Additions to long-lived assets	335	328	(90)
Transfers from non-operating properties	(8)	415	1,622
Segment assets	21,293	70,914	73,309
Segment assets [Member]
Segment financial information for real estate operations
Segment assets	$ 3,004,247	$ 3,265,469	$ 2,951,495