Significant Tenants	9 Months Ended
Sep. 30, 2011
Significant Tenants [Abstract]
Significant Tenants	10. Significant Tenants Bloomberg L.P. (“Bloomberg”) accounted for $63,289,000 and $62,476,000, or 33% and 35% of our consolidated revenues in the nine months ended September 30, 2011 and 2010, respectively. No other tenant accounted for more than 10% of our consolidated revenues. If we were to lose Bloomberg as a tenant, or if Bloomberg were to fail or become unable to perform its obligations under its lease, it would adversely affect our results of operations and financial condition. We receive and evaluate certain confidential financial information and metrics from Bloomberg on a semi-annual basis. In addition, we access and evaluate financial information regarding Bloomberg from private sources, as well as publicly available data.

The entire disclosure for any concentrations existing at the date of the financial statements that make an entity vulnerable to a reasonably possible, near-term, severe impact. This disclosure informs financial statement users about the general nature of the risk associated with the concentration, and may indicate the percentage of concentration risk as of the balance sheet date.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 275

-SubTopic 10

-Section 50

-Paragraph 20

-URI http://asc.fasb.org/extlink&oid=6927468&loc=d3e6404-108592

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Statement of Position (SOP)

-Number 94-6

-Paragraph 21, 22, 24

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 21

-URI http://asc.fasb.org/extlink&oid=6947722&loc=d3e13537-108611

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 107

-Paragraph 15A

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 275

-SubTopic 10

-Section 50

-Paragraph 21

-URI http://asc.fasb.org/extlink&oid=6927468&loc=d3e6442-108592

Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 20

-URI http://asc.fasb.org/extlink&oid=6947722&loc=d3e13531-108611

Reference 7: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 275

-SubTopic 10

-Section 50

-Paragraph 16

-URI http://asc.fasb.org/extlink&oid=6927468&loc=d3e6327-108592

Reference 8: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 275

-SubTopic 10

-Section 50

-Paragraph 18

-URI http://asc.fasb.org/extlink&oid=6927468&loc=d3e6351-108592

+ Details