Commitments and Contingencies (Detail) (USD $)	Dec. 31, 2014
Commitments and Contingencies.
Amount of contingent obligations for tenant improvements and leasing costs	$ 735,000
Amount of commitments for construction contracts, which is expected to be paid in next twelve months	33,600,000
Minimum future rental payments for the next five years and thereafter under ground leases
2015	13,700,000
2016	13,700,000
2017	13,800,000
2018	13,800,000
2019	13,600,000
Thereafter	140,300,000
Total	208,900,000
Realty Income
Minimum future rental payments for the next five years and thereafter under ground leases
2015	1,000,000
2016	1,000,000
2017	1,000,000
2018	1,000,000
2019	900,000
Thereafter	8,400,000
Total	13,300,000
Tenants
Minimum future rental payments for the next five years and thereafter under ground leases
2015	12,700,000
2016	12,700,000
2017	12,800,000
2018	12,800,000
2019	12,700,000
Thereafter	131,900,000
Total	$ 195,600,000

General description of commitments required in performing under construction-type contracts at the balance sheet date.

No definition available.

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The amount of contingent payments for tenant improvements and leasing costs for the entity at date of balance sheet.

+ References

No definition available.

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Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 20

-Section 50

-Paragraph 2

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6453985&loc=d3e41502-112717

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 10

-Section 55

-Paragraph 40

-Subparagraph (Note 3)

-URI http://asc.fasb.org/extlink&oid=6584154&loc=d3e38371-112697

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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