Represents the number of leases.

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Amount of required minimum rental payments maturing after the tenth fiscal year following the latest fiscal year for operating leases having initial or remaining non-cancelable letter-terms in excess of one year.

+ References

No definition available.

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Amount of required minimum rental payments maturing in the eighth fiscal year following the latest fiscal year for operating leases having initial or remaining non-cancelable letter-terms in excess of one year.

+ References

No definition available.

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Amount of required minimum rental payments maturing in the ninth fiscal year following the latest fiscal year for operating leases having initial or remaining non-cancelable letter-terms in excess of one year.

+ References

No definition available.

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Amount of required minimum rental payments maturing in the seventh fiscal year following the latest fiscal year for operating leases having initial or remaining non-cancelable letter-terms in excess of one year.

+ References

No definition available.

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- Definition

Amount of required minimum rental payments maturing in the sixth fiscal year following the latest fiscal year for operating leases having initial or remaining non-cancelable letter-terms in excess of one year.

+ References

No definition available.

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Amount of required minimum rental payments maturing in the tenth fiscal year following the latest fiscal year for operating leases having initial or remaining non-cancelable letter-terms in excess of one year.

+ References

No definition available.

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- Definition

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

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-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 03
-Paragraph 12
-Article 7

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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- Definition

Amount of debt for which creditor does not have general recourse to the debtor but rather has recourse only to the property used for collateral in the transaction or other specific property.

+ References

No definition available.

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- Definition

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

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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No definition available.

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- Definition

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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- Definition

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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Leasing Activity (Details) $ in Thousands	12 Months Ended
Leasing Activity (Details) $ in Thousands	Dec. 31, 2015 USD ($) lease	Dec. 31, 2014 USD ($)	Dec. 31, 2013	Jan. 12, 2016
Future Minimum Base Rental Payments
2016	$ 13,165
2017	11,954
2018	5,312
2019	3,751
2020	2,994
2021	2,364
2022	1,913
2023	1,511
2024	976
2025	957
Thereafter	660
Total	$ 45,557
Number of leases \| lease	1
Concentration Risk, Percentage	100.00%	100.00%	100.00%
Assets	$ 307,802	$ 314,492
Office Building [Member] \| Customer Concentration Risk [Member]
Future Minimum Base Rental Payments
Concentration Risk, Percentage	10.00%
Sales [Member] \| Geographic Concentration Risk [Member]
Future Minimum Base Rental Payments
Concentration Risk, Percentage	10.00%
Northborough Tower [Member]
Future Minimum Base Rental Payments
Non-Recourse Debt	$ 18,500
Assets	$ 15,200
Chase Park Plaza [Member] \| Sales [Member] \| Geographic Concentration Risk [Member]
Future Minimum Base Rental Payments
Concentration Risk, Percentage	60.00%
Frisco Square [Member] \| Sales [Member] \| Geographic Concentration Risk [Member]
Future Minimum Base Rental Payments
Concentration Risk, Percentage	14.00%
Northborough Tower [Member] \| Sales [Member] \| Geographic Concentration Risk [Member]
Future Minimum Base Rental Payments
Concentration Risk, Percentage	11.00%
Subsequent Event \| Northborough Tower [Member]
Future Minimum Base Rental Payments
Notes payable, interest rates (as a percent)				8.67%