Operating and Direct Financing Leases - Schedule of Estimated Future Minimum Rental Payments to be Received and Paid Under Lease Contracts (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012
Head Lease Receipts [Member]
Operating Leased Assets [Line Items]
2013	$ 28,843
2014	28,828
2015	22,188
2016	21,242
2017	21,242
Thereafter	239,063
Total	361,406
Sublease Payments [Member]
Operating Leased Assets [Line Items]
2013	24,779
2014	24,779
2015	24,779
2016	24,779
2017	24,779
Thereafter	278,884
Total	$ 402,779

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Future minimum rental payments in aggregate as of the balance sheet date under operating leases.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 20

-Section 50

-Paragraph 4

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6454179&loc=d3e41551-112718

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 13

-Paragraph 23

-Subparagraph b(ii)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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- Definition

Future rental payments receivable within one year of the balance sheet date under an operating lease.

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+ Details

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- Definition

Future rental payments receivable within the fifth year from the balance sheet date under an operating lease.

+ References

+ Details

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- Definition

Future rental payments receivable within the fourth year from the balance sheet date under an operating lease.

+ References

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- Definition

Future rental payments receivable within the third year from the balance sheet date under an operating lease.

+ References

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- Definition

Future rental payments receivable within the second year from the balance sheet date under an operating lease.

+ References

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- Definition

Future minimum lease payments receivable under operating leases for periods greater than five years following the balance sheet date.

+ References

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