Receivables - Receivables (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Accounts, Notes, Loans and Financing Receivable [Line Items]
Receivables, gross	$ 23,893	$ 24,847
Oil and gas joint interest billing receivables	867	5,738
Allowance for bad debts	(237)	(258)
Receivables, net	23,656	24,589
Loan secured by real estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Receivables, gross	0	3,574
Other loans secured by real estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Receivables, gross	$ 2,130	$ 1,737
Average Interest Rates	11.31%	4.41%
Oil and gas revenue accrual receivable [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Receivables, gross	$ 3,745	$ 7,293
Other receivables and accrued interest [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Receivables, gross	$ 2,448	$ 6,505

Accounts and notes receivable gross.

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- Definition

Average interest rates.

+ References

No definition available.

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- Definition

Carrying amount as of the balance sheet date, net of allowance for doubtful accounts, of account and note receivables due from other than related parties.

+ References

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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.

+ Details

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- Definition

A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible.

+ 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 210.5-02.4)
-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 310
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=49124121&loc=d3e5074-111524

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- Definition

Portion of accounts receivable attributable to joint interest partners in oil and gas properties. These are billings to the non-operators associated with the operation of wells and are based on those owners' working interests in the wells.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-SubTopic 323
-Section 25
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6474814&loc=d3e64006-109457

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