Segment Information (Details) (USD $) In Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Property rentals	$ 530,086	$ 526,776	$ 1,604,451	$ 1,560,473
Straight Line Rent Adjustments	14,963	15,986	34,713	53,018
Amortization of acquired below-market leases, net	16,100	16,756	49,387	48,476
Total rentals	561,149	559,518	1,688,551	1,661,967
Tenant expense reimbursements	94,053	95,341	264,857	271,040
Cleveland Medical Mart development project	35,135	0	108,203	0
Tenant cleaning fees	15,647	13,613	46,479	40,733
Management and leasing fees	4,361	3,555	15,456	16,075
Lease termination fees	4,803	2,301	12,478	10,112
Other	12,195	12,797	37,826	37,918
Total Revenues	727,343	687,125	2,173,850	2,037,845
Operating expenses	285,659	275,077	841,266	802,927
Depreciation and amortization	134,074	130,599	393,846	393,259
General and administrative	46,452	55,200	155,566	153,231
Cleveland Medical Mart development project	33,419	0	101,637	0
Tenant buy-outs and other acquisition related costs	2,288	921	22,455	2,851
Total expenses	501,892	461,797	1,514,770	1,352,268
Operating income	225,451	225,328	659,080	685,577
Income (loss) from partially owned entities	4,248	(4,553)	137,033	116,109
Income (loss) from Real Estate Fund (of which $3,675 and $1,091 is attributable to noncontrolling interests, in each three-month period, respectively, and $15,703 and $1,091 in each nine-month period, respectively)	5,353	(1,410)	25,491	(1,410)
Interest and other investment (loss) income, net	(29,994)	47,096	95,121	65,676
Interest and debt expense (including amortization of deferred financing costs of $4,828 and $5,170 in each three-month period, respectively, and $14,696 and $14,085 in each nine-month period, respectively)	(136,672)	(145,561)	(408,532)	(423,354)
Net gain on early extinguishment of debt	0	(724)	0	(1,796)
Net gain on disposition of wholly owned and partially owned assets	1,298	5,072	7,975	12,759
Income loss before income taxes	69,684	125,248	516,168	453,561
Income tax expense	(7,144)	(5,449)	(19,448)	(15,993)
Income from continuing operations	62,540	119,799	496,720	437,568
Income (loss) from discontinued operations	3,683	(3,667)	146,293	(11,681)
Net income	66,223	116,132	643,013	425,887
Net (income) loss attributable to noncontrolling interests in consolidated subsidiaries	(5,636)	(296)	(20,643)	(1,490)
Net income attributable to noncontrolling interests in the Operating Partnership, including unit distributions	(6,825)	(11,584)	(47,364)	(33,487)
Net income (loss) attributable to Vornado	53,762	104,252	575,006	390,910
Interest and debt expense (2)	197,864	208,294	599,668	611,993
Depreciation and amortization (2)	193,394	179,148	561,738	549,400
Income tax expense	(7,350)	(23,013)	42,135	13,553
EBITDA	437,670	468,681	1,778,547	1,565,856
Toys R Us [Member] | New York Office [Member]
Income (loss) from partially owned entities	0	0	0	0
All Equity Method Investees Excluding Toys [Member] | New York Office [Member]
Income (loss) from partially owned entities	(5,136)	1,705	(4,893)	4,345
New York Office [Member]
Property rentals	196,123	194,815	586,797	582,090
Straight Line Rent Adjustments	3,998	7,573	15,777	22,642
Amortization of acquired below-market leases, net	8,153	8,936	24,549	27,312
Total rentals	208,274	211,324	627,123	632,044
Tenant expense reimbursements	43,025	40,387	108,267	105,968
Cleveland Medical Mart development project	0		0
Tenant cleaning fees	24,047	21,721	71,156	62,778
Management and leasing fees	1,653	1,428	5,260	4,278
Lease termination fees	3,540	1,220	9,176	4,245
Other	5,212	5,505	15,078	14,428
Total Revenues	285,751	281,585	836,060	823,741
Operating expenses	129,472	124,152	367,291	349,934
Depreciation and amortization	47,038	44,131	138,837	131,911
General and administrative	4,461	4,504	14,389	13,824
Cleveland Medical Mart development project	0		0
Tenant buy-outs and other acquisition related costs	0	0	0	0
Total expenses	180,971	172,787	520,517	495,669
Operating income	104,780	108,798	315,543	328,072
Income (loss) from partially owned entities	(5,136)	1,705	(4,893)	4,345
Income (loss) from Real Estate Fund (of which $3,675 and $1,091 is attributable to noncontrolling interests, in each three-month period, respectively, and $15,703 and $1,091 in each nine-month period, respectively)	0		0
Interest and other investment (loss) income, net	146	139	466	466
Interest and debt expense (including amortization of deferred financing costs of $4,828 and $5,170 in each three-month period, respectively, and $14,696 and $14,085 in each nine-month period, respectively)	(35,395)	(33,293)	(103,514)	(99,026)
Net gain on early extinguishment of debt		0
Net gain on disposition of wholly owned and partially owned assets	0	0	0	0
Income loss before income taxes	64,395	77,349	207,602	233,857
Income tax expense	(678)	(861)	(1,637)	(1,670)
Income from continuing operations	63,717	76,488	205,965	232,187
Income (loss) from discontinued operations	165	30	398	106
Net income	63,882	76,518	206,363	232,293
Net (income) loss attributable to noncontrolling interests in consolidated subsidiaries	(2,219)	(2,442)	(6,815)	(7,290)
Net income attributable to noncontrolling interests in the Operating Partnership, including unit distributions	0	0	0	0
Net income (loss) attributable to Vornado	61,663	74,076	199,548	225,003
Interest and debt expense (2)	39,526	31,817	108,473	94,404
Depreciation and amortization (2)	53,936	42,531	146,650	127,341
Income tax expense	736	861	1,695	1,670
EBITDA	155,861	149,285	456,366	448,418
Toys R Us [Member] | Washington DC Office [Member]
Income (loss) from partially owned entities	0	0	0	0
All Equity Method Investees Excluding Toys [Member] | Washington DC Office [Member]
Income (loss) from partially owned entities	(1,356)	(1,095)	(6,038)	(1,099)
Washington DC Office [Member]
Property rentals	133,156	146,439	413,810	426,217
Straight Line Rent Adjustments	6,673	347	5,962	5,519
Amortization of acquired below-market leases, net	547	594	1,525	1,836
Total rentals	140,376	147,380	421,297	433,572
Tenant expense reimbursements	9,328	15,129	27,561	42,592
Cleveland Medical Mart development project	0		0
Tenant cleaning fees	0	0	0	0
Management and leasing fees	2,670	2,772	9,629	13,252
Lease termination fees	1,002	728	3,013	1,256
Other	5,232	5,554	15,894	16,452
Total Revenues	158,608	171,563	477,394	507,124
Operating expenses	51,791	58,327	150,375	163,097
Depreciation and amortization	33,885	36,764	101,634	108,994
General and administrative	6,505	5,984	19,504	18,079
Cleveland Medical Mart development project	0		0
Tenant buy-outs and other acquisition related costs	0	0	0	0
Total expenses	92,181	101,075	271,513	290,170
Operating income	66,427	70,488	205,881	216,954
Income (loss) from partially owned entities	(1,356)	(1,095)	(6,038)	(1,099)
Income (loss) from Real Estate Fund (of which $3,675 and $1,091 is attributable to noncontrolling interests, in each three-month period, respectively, and $15,703 and $1,091 in each nine-month period, respectively)	0		0
Interest and other investment (loss) income, net	39	81	119	130
Interest and debt expense (including amortization of deferred financing costs of $4,828 and $5,170 in each three-month period, respectively, and $14,696 and $14,085 in each nine-month period, respectively)	(30,256)	(33,367)	(89,911)	(101,592)
Net gain on early extinguishment of debt		0
Net gain on disposition of wholly owned and partially owned assets	0	0	0	0
Income loss before income taxes	34,854	36,107	110,051	114,393
Income tax expense	(960)	(1,001)	(2,267)	(1,092)
Income from continuing operations	33,894	35,106	107,784	113,301
Income (loss) from discontinued operations	0	1,410	46,466	(5,776)
Net income	33,894	36,516	154,250	107,525
Net (income) loss attributable to noncontrolling interests in consolidated subsidiaries	0	0	0	0
Net income attributable to noncontrolling interests in the Operating Partnership, including unit distributions	0	0	0	0
Net income (loss) attributable to Vornado	33,894	36,516	154,250	107,525
Interest and debt expense (2)	33,703	34,241	100,017	104,355
Depreciation and amortization (2)	38,085	41,394	118,290	120,929
Income tax expense	925	1,054	2,380	1,161
EBITDA	106,607	113,205	374,937	333,970
Toys R Us [Member] | Retail [Member]
Income (loss) from partially owned entities	0	0	0	0
All Equity Method Investees Excluding Toys [Member] | Retail [Member]
Income (loss) from partially owned entities	889	833	2,131	3,353
Retail [Member]
Property rentals	105,788	97,625	316,729	284,808
Straight Line Rent Adjustments	4,696	7,441	12,556	21,699
Amortization of acquired below-market leases, net	6,268	5,820	19,899	14,897
Total rentals	116,752	110,886	349,184	321,404
Tenant expense reimbursements	36,297	35,688	111,519	107,799
Cleveland Medical Mart development project	0		0
Tenant cleaning fees	0	0	0	0
Management and leasing fees	541	214	2,439	759
Lease termination fees	261	346	289	4,182
Other	1,155	1,016	4,241	2,284
Total Revenues	155,006	148,150	467,672	436,428
Operating expenses	57,412	52,309	173,623	159,131
Depreciation and amortization	30,080	26,329	85,653	80,550
General and administrative	6,721	8,843	22,034	22,591
Cleveland Medical Mart development project	0		0
Tenant buy-outs and other acquisition related costs	1,593	0	16,593	0
Total expenses	95,806	87,481	297,903	262,272
Operating income	59,200	60,669	169,769	174,156
Income (loss) from partially owned entities	889	833	2,131	3,353
Income (loss) from Real Estate Fund (of which $3,675 and $1,091 is attributable to noncontrolling interests, in each three-month period, respectively, and $15,703 and $1,091 in each nine-month period, respectively)	0		0
Interest and other investment (loss) income, net	3	(46)	5	143
Interest and debt expense (including amortization of deferred financing costs of $4,828 and $5,170 in each three-month period, respectively, and $14,696 and $14,085 in each nine-month period, respectively)	(23,176)	(24,199)	(69,482)	(62,047)
Net gain on early extinguishment of debt		0
Net gain on disposition of wholly owned and partially owned assets	0	0	0	0
Income loss before income taxes	36,916	37,257	102,423	115,605
Income tax expense	0	(2)	(5)	(37)
Income from continuing operations	36,916	37,255	102,418	115,568
Income (loss) from discontinued operations	818	(3,642)	9,217	(1,539)
Net income	37,734	33,613	111,635	114,029
Net (income) loss attributable to noncontrolling interests in consolidated subsidiaries	110	397	196	895
Net income attributable to noncontrolling interests in the Operating Partnership, including unit distributions	0	0	0	0
Net income (loss) attributable to Vornado	37,844	34,010	111,831	114,924
Interest and debt expense (2)	24,368	26,395	73,000	68,275
Depreciation and amortization (2)	30,946	28,024	88,322	85,335
Income tax expense	0	2	5	37
EBITDA	93,158	88,431	273,158	268,571
Toys R Us [Member] | Merchandise Mart [Member]
Income (loss) from partially owned entities	0	0	0	0
All Equity Method Investees Excluding Toys [Member] | Merchandise Mart [Member]
Income (loss) from partially owned entities	38	8	292	239
Merchandise Mart [Member]
Property rentals	46,278	42,774	154,485	145,206
Straight Line Rent Adjustments	(1,006)	(457)	(2,059)	628
Amortization of acquired below-market leases, net	21	15	55	(91)
Total rentals	45,293	42,332	152,481	145,743
Tenant expense reimbursements	2,972	2,784	9,121	8,876
Cleveland Medical Mart development project	35,135		108,203
Tenant cleaning fees	0	0	0	0
Management and leasing fees	45	(2)	348	31
Lease termination fees	0	7	0	429
Other	988	800	2,832	3,471
Total Revenues	84,433	45,921	272,985	158,550
Operating expenses	30,803	26,391	99,266	85,915
Depreciation and amortization	10,372	9,853	29,113	30,111
General and administrative	9,534	6,010	23,855	20,252
Cleveland Medical Mart development project	33,419		101,637
Tenant buy-outs and other acquisition related costs	0	0	3,040	0
Total expenses	84,128	42,254	256,911	136,278
Operating income	305	3,667	16,074	22,272
Income (loss) from partially owned entities	38	8	292	239
Income (loss) from Real Estate Fund (of which $3,675 and $1,091 is attributable to noncontrolling interests, in each three-month period, respectively, and $15,703 and $1,091 in each nine-month period, respectively)	0		0
Interest and other investment (loss) income, net	17	11	35	35
Interest and debt expense (including amortization of deferred financing costs of $4,828 and $5,170 in each three-month period, respectively, and $14,696 and $14,085 in each nine-month period, respectively)	(9,365)	(9,556)	(28,140)	(28,383)
Net gain on early extinguishment of debt		0
Net gain on disposition of wholly owned and partially owned assets	0	0	0	765
Income loss before income taxes	(9,005)	(5,870)	(11,739)	(5,072)
Income tax expense	(890)	714	(2,211)	118
Income from continuing operations	(9,895)	(5,156)	(13,950)	(4,954)
Income (loss) from discontinued operations	2,700	(1,465)	90,212	(4,472)
Net income	(7,195)	(6,621)	76,262	(9,426)
Net (income) loss attributable to noncontrolling interests in consolidated subsidiaries	0	0	0	0
Net income attributable to noncontrolling interests in the Operating Partnership, including unit distributions	0	0	0	0
Net income (loss) attributable to Vornado	(7,195)	(6,621)	76,262	(9,426)
Interest and debt expense (2)	9,523	15,883	32,025	45,370
Depreciation and amortization (2)	12,230	12,782	34,632	39,049
Income tax expense	890	(714)	2,211	(59)
EBITDA	15,448	21,330	145,130	74,934
Toys R Us [Member] | Toys R Us Segment [Member]
Income (loss) from partially owned entities	(9,304)	(2,557)	80,794	102,309
All Equity Method Investees Excluding Toys [Member] | Toys R Us Segment [Member]
Income (loss) from partially owned entities	0		0	0
Toys R Us Segment [Member]
Property rentals	0	0	0	0
Straight Line Rent Adjustments	0	0	0	0
Amortization of acquired below-market leases, net	0	0	0	0
Total rentals	0	0	0	0
Tenant expense reimbursements	0	0	0	0
Cleveland Medical Mart development project	0		0
Tenant cleaning fees	0	0	0	0
Management and leasing fees	0	0	0	0
Lease termination fees	0	0	0	0
Other	0	0	0	0
Total Revenues	0	0	0	0
Operating expenses	0	0	0	0
Depreciation and amortization	0	0	0	0
General and administrative	0	0	0	0
Cleveland Medical Mart development project	0		0
Tenant buy-outs and other acquisition related costs	0	0	0	0
Total expenses	0	0	0	0
Operating income	0	0	0	0
Income (loss) from partially owned entities	(9,304)	(2,557)	80,794	102,309
Income (loss) from Real Estate Fund (of which $3,675 and $1,091 is attributable to noncontrolling interests, in each three-month period, respectively, and $15,703 and $1,091 in each nine-month period, respectively)	0		0
Interest and other investment (loss) income, net	0	0	0	0
Interest and debt expense (including amortization of deferred financing costs of $4,828 and $5,170 in each three-month period, respectively, and $14,696 and $14,085 in each nine-month period, respectively)	0	0	0	0
Net gain on early extinguishment of debt		0
Net gain on disposition of wholly owned and partially owned assets	0	0	0	0
Income loss before income taxes	(9,304)	(2,557)	80,794	102,309
Income tax expense	0	0	0	0
Income from continuing operations	(9,304)	(2,557)	80,794	102,309
Income (loss) from discontinued operations	0	0	0	0
Net income	(9,304)	(2,557)	80,794	102,309
Net (income) loss attributable to noncontrolling interests in consolidated subsidiaries	0	0	0	0
Net income attributable to noncontrolling interests in the Operating Partnership, including unit distributions	0	0	0	0
Net income (loss) attributable to Vornado	(9,304)	(2,557)	80,794	102,309
Interest and debt expense (2)	38,018	40,558	121,546	123,791
Depreciation and amortization (2)	34,293	30,079	101,862	99,850
Income tax expense	(15,135)	(27,501)	29,914	(1,914)
EBITDA	47,872	40,579	334,116	324,036
Toys R Us [Member] | Other Segment [Member]
Income (loss) from partially owned entities	0	0	0	0
All Equity Method Investees Excluding Toys [Member] | Other Segment [Member]
Income (loss) from partially owned entities	19,117	(3,447)	64,747	6,962
Other Segment [Member]
Property rentals	48,741	45,123	132,630	122,152
Straight Line Rent Adjustments	602	1,082	2,477	2,530
Amortization of acquired below-market leases, net	1,111	1,391	3,359	4,522
Total rentals	50,454	47,596	138,466	129,204
Tenant expense reimbursements	2,431	1,353	8,389	5,805
Cleveland Medical Mart development project	0		0
Tenant cleaning fees	(8,400)	(8,108)	(24,677)	(22,045)
Management and leasing fees	(548)	(857)	(2,220)	(2,245)
Lease termination fees	0	0	0	0
Other	(392)	(78)	(219)	1,283
Total Revenues	43,545	39,906	119,739	112,002
Operating expenses	16,181	13,898	50,711	44,850
Depreciation and amortization	12,699	13,522	38,609	41,693
General and administrative	19,231	29,859	75,784	78,485
Cleveland Medical Mart development project	0		0
Tenant buy-outs and other acquisition related costs	695	921	2,822	2,851
Total expenses	48,806	58,200	167,926	167,879
Operating income	(5,261)	(18,294)	(48,187)	(55,877)
Income (loss) from partially owned entities	19,117	(3,447)	64,747	6,962
Income (loss) from Real Estate Fund (of which $3,675 and $1,091 is attributable to noncontrolling interests, in each three-month period, respectively, and $15,703 and $1,091 in each nine-month period, respectively)	5,353	(1,410)	25,491	(1,410)
Interest and other investment (loss) income, net	(30,199)	46,911	94,496	64,902
Interest and debt expense (including amortization of deferred financing costs of $4,828 and $5,170 in each three-month period, respectively, and $14,696 and $14,085 in each nine-month period, respectively)	(38,480)	(45,146)	(117,485)	(132,306)
Net gain on early extinguishment of debt		(724)		(1,796)
Net gain on disposition of wholly owned and partially owned assets	1,298	5,072	7,975	11,994
Income loss before income taxes	(48,172)	(17,038)	27,037	(107,531)
Income tax expense	(4,616)	(4,299)	(13,328)	(13,312)
Income from continuing operations	(52,788)	(21,337)	13,709	(120,843)
Income (loss) from discontinued operations	0	0	0	0
Net income	(52,788)	(21,337)	13,709	(120,843)
Net (income) loss attributable to noncontrolling interests in consolidated subsidiaries	(3,527)	1,749	(14,024)	4,905
Net income attributable to noncontrolling interests in the Operating Partnership, including unit distributions	(6,825)	(11,584)	(47,364)	(33,487)
Net income (loss) attributable to Vornado	(63,140)	(31,172)	(47,679)	(149,425)
Interest and debt expense (2)	52,726	59,400	164,607	175,798
Depreciation and amortization (2)	23,904	24,338	71,982	76,896
Income tax expense	5,234	3,285	5,930	12,658
EBITDA	18,724	55,851	194,840	115,927
Toys R Us [Member]
Income (loss) from partially owned entities	(9,304)	(2,557)	80,794	102,309
All Equity Method Investees Excluding Toys [Member]
Income (loss) from partially owned entities	$ 13,552	$ (1,996)	$ 56,239	$ 13,800