Percentage points added to the reference rate to compute the variable rate on the debt instrument.

No definition available.

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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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.

+ References

+ Details

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

+ Details

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- Definition

Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28555-108399

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.17)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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-Section S99
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-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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-Publisher FASB
-Name Accounting Standards Codification
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-Section S99
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-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

The number of real estate properties owned as of the balance sheet date.

+ References

No definition available.

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NOTES PAYABLE (Schedule of Long-term Debt Instruments) (Details) $ in Thousands		3 Months Ended
	Mar. 29, 2018 USD ($)	Mar. 31, 2018 USD ($) property	Dec. 31, 2017 USD ($)
Debt Instrument [Line Items]
Total notes payable principal outstanding		$ 512,541	$ 502,633
Deferred financing costs, net		(2,693)	(334)
Total notes payable, net		$ 509,848	502,299
Office Buildings, Campus
Debt Instrument [Line Items]
Number of real estate properties \| property		8
Held-for-sale \| Office Buildings, Campus
Debt Instrument [Line Items]
Number of real estate properties \| property		2
Mortgage \| Amended and Restated Portfolio Revolving Loan Facility
Debt Instrument [Line Items]
Total notes payable principal outstanding		$ 0	52,638
Mortgage \| Union Bank Plaza Mortgage Loan
Debt Instrument [Line Items]
Total notes payable principal outstanding		0	105,000
Mortgage \| Portfolio Mortgage Loan 1
Debt Instrument [Line Items]
Total notes payable principal outstanding		0	59,651
Mortgage \| Portfolio Mortgage Loan 3
Debt Instrument [Line Items]
Total notes payable principal outstanding		0	54,000
Mortgage \| Corporate Technology Centre Mortgage Loan
Debt Instrument [Line Items]
Total notes payable principal outstanding		$ 137,541	138,219
Contractual Interest Rate		3.50%
Effective Interest Rate		3.50%
Maturity Date		Apr. 01, 2020
Mortgage \| 300-600 Campus Drive Revolving Loan
Debt Instrument [Line Items]
Total notes payable principal outstanding		$ 0	93,125
Mortgage \| Portfolio Loan Facility
Debt Instrument [Line Items]
Total notes payable principal outstanding		$ 375,000	$ 0
Total notes payable, net	$ 375,000
Effective Interest Rate		3.30%
Maturity Date		Mar. 29, 2020
Mortgage \| Portfolio Loan Facility \| One-month LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate	1.45%	1.45%