Indebtedness - Scheduled Principal Repayments and Term-loan Maturities (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014
Debt Instrument [Line Items]
Scheduled Principal Payment	$ 76,198
Term-Loan Maturities	284,473
Total Payments	360,671
2015 [Member]
Debt Instrument [Line Items]
Scheduled Principal Payment	3,222
Term-Loan Maturities	8,681
Total Payments	11,903
2016 [Member]
Debt Instrument [Line Items]
Scheduled Principal Payment	3,499
Term-Loan Maturities	104,300
Total Payments	107,799
2017 [Member]
Debt Instrument [Line Items]
Scheduled Principal Payment	2,775
Term-Loan Maturities	116,141
Total Payments	118,916
2018 [Member]
Debt Instrument [Line Items]
Scheduled Principal Payment	1,808
Term-Loan Maturities	44,674
Total Payments	46,482
2019 [Member]
Debt Instrument [Line Items]
Scheduled Principal Payment	1,216
Term-Loan Maturities	9,333
Total Payments	10,549
Thereafter [Member]
Debt Instrument [Line Items]
Scheduled Principal Payment	63,678
Term-Loan Maturities	1,344
Total Payments	$ 65,022

Secured Debt Excluding Unamortized Fair Value Adjustments

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- Definition

Amount of the required periodic payments including both interest and principal payments.

+ 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 SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 470

-Section 50

-Paragraph 3

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=6479336&loc=d3e64711-112823

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