Related-Party Transactions - Rent Income - Schedule of Future Minimum Rental Income (Detail) (USD $)	Dec. 31, 2012
Operating Leased Assets [Line Items]
2013	$ 3,860,000
2014	3,860,000
2015	28,000
2016	28,000
2017	28,000
Thereafter	996,000
Future minimum rental payments due, Total	$ 8,800,000

Amount of minimum lease payments for capital leases.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 30

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6455398&loc=d3e45280-112737

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 13

-Paragraph 16

-Subparagraph a(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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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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Amount of minimum lease payments maturing in the fifth fiscal year following the latest fiscal year for capital leases.

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