4. Debt ACC3 Term Loan (Details) $ in Thousands	3 Months Ended
Mar. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Debt Instrument [Line Items]
Mortgage notes payable	$ 114,183	$ 114,075
AccThreeTermLoan [Member]
Debt Instrument [Line Items]
Mortgage notes payable	$ 115,000
Debt Instrument, Maturity Date	Mar. 27, 2018
AccThreeTermLoan [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Ratio of Total Indebtedness To Gross Assets Value	60.00%
AccThreeTermLoan [Member] \| Minimum [Member]
Debt Instrument [Line Items]
Fixed Charge Coverage Ratio	1.70
Tangible Net Worth Amount	$ 1,300,000
Percentage Of Equity Offerings And Interests In Operating Partnerships To Be Added To Tangible Net Worth Threshold	80.00%
Debt Service Coverage Ratio	1.50
AccThreeTermLoan [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate	1.55%
AccThreeTermLoan [Member] \| Base Rate [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate	0.55%

Consolidated Total Indebtedness To Gross Assets Value Ratio

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- Definition

Debt service coverage ratio.

+ References

No definition available.

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- Definition

Fixed charge coverage ratio.

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- Definition

Percentage of equity offerings and interests in operating partnerships to be added to tangible net worth threshold.

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No definition available.

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- Definition

Tangible net worth amount.

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- Definition

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

+ References

No definition available.

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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

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(a)(2))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Carrying value as of the balance sheet date, including the current and noncurrent portions, of collateralized debt obligations (with maturities initially due after one year or beyond the operating cycle, if longer). Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower.

+ References

Reference 1: 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

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.16)
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 19, 20, 22
-Article 5

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