PrimeEnergy Resources (PNRG) 10-Q 5 Nov 13 2013 Q3 Quarterly report Financial data

Document_and_Entity_Informatio

Document and Entity Information	9 Months Ended
	Sep. 30, 2013	Oct. 30, 2013
Document And Entity Information [Abstract]	'	'
Document Type	'10-Q	'
Amendment Flag	'false	'
Document Period End Date	30-Sep-13	'
Document Fiscal Year Focus	'2013	'
Document Fiscal Period Focus	'Q3	'
Trading Symbol	'PNRG	'
Entity Registrant Name	'PRIMEENERGY CORPORATION	'
Entity Central Index Key	'0000056868	'
Current Fiscal Year End Date	'--12-31	'
Entity Filer Category	'Smaller Reporting Company	'
Entity Common Stock, Shares Outstanding	'	2,405,879

Condensed_Consolidated_Balance

Condensed Consolidated Balance Sheets (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Current Assets	'	'
Cash and cash equivalents	$11,522	$8,602
Restricted cash and cash equivalents	3,265	4,672
Accounts receivable, net	17,722	13,212
Other current assets	2,964	3,966
Total Current Assets	35,473	30,452
Property and Equipment, at cost	'	'
Oil and gas properties (successful efforts method), net	190,463	187,928
Field and office equipment, net	10,992	8,922
Total Property and Equipment, Net	201,455	196,850
Other Assets	1,569	784
Total Assets	238,497	228,086
Current Liabilities	'	'
Accounts payable	17,799	19,568
Accrued liabilities	8,131	7,618
Current portion of long-term debt	1,852	'
Current portion of asset retirement and other long-term obligations	3,324	2,148
Derivative liability short-term	2,760	994
Due to related parties	134	67
Total Current Liabilities	34,000	30,395
Long-Term Bank Debt	114,997	122,000
Asset Retirement Obligations	7,116	6,864
Derivative Liability Long-Term	209	431
Deferred Income Taxes	29,627	24,194
Total Liabilities	185,949	183,884
Commitments and Contingencies	'	'
Equity	'	'
Common stock, $.10 par value; Authorized: 4,000,000 shares, issued: 3,836,397 shares	383	383
Paid-in capital	6,745	6,690
Retained earnings	76,929	66,345
Accumulated other comprehensive loss, net	-56	-35
Treasury stock, at cost; 1,423,519 shares and 1,325,837 shares	-39,090	-36,113
Total Stockholders' Equity - PrimeEnergy	44,911	37,270
Non-controlling interest	7,637	6,932
Total Equity	52,548	44,202
Total Liabilities and Equity	$238,497	$228,086

Condensed_Consolidated_Balance1

Condensed Consolidated Balance Sheets (Parenthetical) (USD $)	Sep. 30, 2013	Dec. 31, 2012
Statement Of Financial Position [Abstract]	'	'
Common stock, par value	$0.10	$0.10
Common stock, shares authorized	4,000,000	4,000,000
Common stock, shares issued	3,836,397	3,836,397
Treasury stock, shares	1,423,519	1,325,837

Condensed_Consolidated_Stateme

Condensed Consolidated Statements of Operations (USD $)	3 Months Ended		9 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Revenues	'	'	'	'
Oil and gas sales	$25,948	$21,813	$71,442	$65,678
Realized gain (loss) on derivative instruments, net	-1,201	38	-1,127	379
Field service income	6,772	4,892	18,348	15,344
Administrative overhead fees	2,319	2,141	6,976	6,415
Unrealized gain (loss) on derivative instruments, net	-3,869	-2,649	-1,472	2,449
Other income	11	25	63	128
Total Revenues	29,980	26,260	94,230	90,393
Costs and Expenses	'	'	'	'
Lease operating expense	11,331	9,347	32,310	28,820
Field service expense	5,521	4,275	15,224	13,023
Depreciation, depletion, amortization and accretion on discounted liabilities	5,177	5,884	16,329	19,846
General and administrative expense	3,864	3,823	12,252	11,509
Exploration costs	2	'	3	10
Total Costs and Expenses	25,895	23,329	76,118	73,208
Gain on Sale and Exchange of Assets	760	14	2,519	720
Income from Operations	4,845	2,945	20,631	17,905
Other Income and Expenses	'	'	'	'
Less: Interest expense	1,000	947	3,158	2,534
Add: Interest income	'	24	2	72
Income Before Provision for Income Taxes	3,845	2,022	17,475	15,443
Provision for Income Taxes	1,227	464	5,935	4,665
Net Income	2,618	1,558	11,540	10,778
Less: Net Income Attributable to Non-Controlling Interests	386	216	956	690
Net Income Attributable to PrimeEnergy	$2,232	$1,342	$10,584	$10,088
Basic Income Per Common Share	$0.92	$0.51	$4.32	$3.81
Diluted Income Per Common Share	$0.71	$0.40	$3.32	$2.98

Condensed_Consolidated_Stateme1

Condensed Consolidated Statements of Comprehensive Income (USD $)	9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012
Statement Of Income And Comprehensive Income [Abstract]	'	'
Net income	$11,540	$10,778
Other Comprehensive Loss, net of taxes:	'	'
Changes in fair value of hedge positions, net of taxes of $12 and $28, respectively	-21	-50
Total other comprehensive loss	-21	-50
Comprehensive Income	11,519	10,728
Less: Comprehensive Income Attributable to Non-Controlling Interest	956	690
Comprehensive Income Attributable to PrimeEnergy	$10,563	$10,038

Condensed_Consolidated_Stateme2

Condensed Consolidated Statements of Comprehensive Income (Parenthetical) (USD $)	9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012
Statement Of Income And Comprehensive Income [Abstract]	'	'
Changes in fair value of hedge positions, tax	$12	$28

Condensed_Consolidated_Stateme3

Condensed Consolidated Statement of Equity (USD $)	Total	Common Stock [Member]	Additional Paid in Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Loss [Member]	Treasury Stock [Member]	Total Stockholders' Equity - PrimeEnergy [Member]	Non-Controlling Interest [Member]
In Thousands, except Share data
Balance at Dec. 31, 2012	$44,202	$383	$6,690	$66,345	($35)	($36,113)	$37,270	$6,932
Balance, shares at Dec. 31, 2012	3,836,397	3,836,397	'	'	'	'	'	'
Repurchase 97,682 shares of common stock	-2,977	'	'	'	'	-2,977	-2,977	'
Net income	11,540	'	'	10,584	'	'	10,584	956
Other comprehensive income, net of taxes	-21	'	'	'	-21	'	-21	'
Repurchase of non-controlling interests	-14	'	55	'	'	'	55	-69
Distributions to non-controlling interests	-182	'	'	'	'	'	'	-182
Balance at Sep. 30, 2013	$52,548	$383	$6,745	$76,929	($56)	($39,090)	$44,911	$7,637
Balance, shares at Sep. 30, 2013	3,836,397	3,836,397	'	'	'	'	'	'

Condensed_Consolidated_Stateme4

Condensed Consolidated Statement of Equity (Parenthetical)	9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013
Repurchase of common stock, shares	97,682
Treasury Stock [Member]	'
Repurchase of common stock, shares	97,682
Total Stockholders' Equity - PrimeEnergy [Member]	'
Repurchase of common stock, shares	97,682

Condensed_Consolidated_Stateme5

Condensed Consolidated Statements of Cash Flows (USD $)	9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012
Cash Flows from Operating Activities:	'	'
Net income	$11,540	$10,778
Adjustments to reconcile net income to net cash provided by operating activities:	'	'
Depreciation, depletion, amortization and accretion on discounted liabilities	16,329	19,846
Gain on sale of properties	-2,519	-720
Unrealized (gain) loss on derivative instruments, net	1,472	-2,449
Provision for deferred income taxes	5,407	4,738
Changes in assets and liabilities:	'	'
Increase in accounts receivable	-4,510	-1,652
Decrease in other assets	253	5,476
Decrease in accounts payable	-362	-3,655
Increase in accrued liabilities	2,988	605
Increase in due to related parties	108	426
Net Cash Provided by Operating Activities	30,706	33,393
Cash Flows from Investing Activities:	'	'
Capital expenditures, including exploration expense	-22,459	-68,620
Proceeds from sale of property and equipment	2,997	881
Net Cash Used in Investing Activities	-19,462	-67,739
Cash Flows from Financing Activities:	'	'
Purchase of stock for treasury	-2,977	-2,705
Purchase of non-controlling interests	-14	-66
Proceeds from long-term bank debt and other long-term obligations	37,250	85,300
Repayment of long-term bank debt and other long-term obligations	-42,401	-45,357
Distribution to non-controlling interests	-182	-867
Net Cash Provided by (Used in) in Financing Activities	-8,324	36,305
Net Increase in Cash and Cash Equivalents	2,920	1,959
Cash and Cash Equivalents at the Beginning of the Period	8,602	8,661
Cash and Cash Equivalents at the End of the Period	11,522	10,620
Supplemental Disclosures:	'	'
Income taxes paid (refunded)	-63	536
Interest paid	$3,187	$2,534

Basis_of_Presentation

Basis of Presentation	9 Months Ended
	Sep. 30, 2013
Accounting Policies [Abstract]	'
Basis of Presentation	'
	(1) Basis of Presentation:
	The accompanying condensed consolidated financial statements of PrimeEnergy Corporation (“PEC” or the “Company”) have not been audited by independent public accountants. Pursuant to applicable Securities and Exchange Commission (“SEC”) rules and regulations, the accompanying interim financial statements do not include all disclosures presented in annual financial statements and the reader should refer to the Company’s Form 10-K for the year ended December 31, 2012. In the opinion of management, the accompanying interim condensed consolidated financial statements contain all material adjustments, consisting only of normal recurring adjustments, necessary for a fair presentation of the Company’s condensed consolidated balance sheets as of September 30, 2013 and December 31, 2012, the condensed consolidated results of operations for the three and nine months ended September 30, 2013 and 2012, and the condensed consolidated results of cash flows and equity for the nine months ended September 30, 2013 and 2012. Certain amounts presented in prior period financial statements have been reclassified for consistency with current period presentation. The results for interim periods are not necessarily indicative of annual results. For purposes of disclosure in the condensed consolidated financial statements, subsequent events have been evaluated through the date the statements were issued.
	Recently Issued Accounting Pronouncements
	In December 2011, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2011-11, “Disclosures about Offsetting Assets and Liabilities.” This ASU requires enhanced disclosures including both gross and net information about financial and derivative instruments eligible for offset or subject to an enforceable master netting arrangement or similar agreement. This new guidance is effective for annual reporting periods beginning on or after January 1, 2013 and subsequent interim periods. In January 2013, the FASB issued ASU 2013-01, “Clarifying the Scope of Disclosures about Offsetting Assets and Liabilities.” ASU 2013-01 clarifies the scope of ASU 2011-11 to apply to derivative instruments that are offset or subject to an enforceable master netting arrangement or similar agreement. This clarified guidance is effective for annual reporting periods beginning on or after January 1, 2013 and subsequent interim periods. The revised requirements of ASU 2011-11 and ASU 2013-01 impacted the disclosures associated with the Company’s derivative instruments (Note 11) and did not have a material impact on the Company’s condensed consolidated financial position, results of operations or cash flows.
	In February 2013, the FASB issued ASU 2013-02, “Reporting of Amounts Reclassified Out of Accumulated Other Comprehensive Income” (“AOCI”). ASU 2013-02 requires a rollforward of changes in AOCI by component and information about significant reclassifications from AOCI to net earnings to be presented in one location, either on the face of the financial statements or in the notes. This new guidance is effective for fiscal years beginning after December 15, 2012 and subsequent interim periods. The revised disclosure requirements of ASU 2013-02 are reflected in Note 11. The requirements of ASU 2013-02 did not have a material impact on the Company’s condensed consolidated financial position, results of operations or cash flows.

Acquisitions_and_Dispositions

Acquisitions and Dispositions	9 Months Ended
	Sep. 30, 2013
Business Combinations [Abstract]	'
Acquisitions and Dispositions	'
	(2) Acquisitions and Dispositions:
	Historically the Company has repurchased the interests of the partners and trust unit holders in the eighteen oil and gas limited partnerships (the “Partnerships”) and the two asset and business income trusts (the “Trusts”) managed by the Company as general partner and as managing trustee, respectively. The Company purchased such interests in amounts totaling $14,000 and $66,000 for the nine months ended September 30, 2013 and 2012, respectively.

Restricted_Cash_and_Cash_Equiv

Restricted Cash and Cash Equivalents	9 Months Ended
	Sep. 30, 2013
Cash And Cash Equivalents [Abstract]	'
Restricted Cash and Cash Equivalents	'
	(3) Restricted Cash and Cash Equivalents:
	Restricted cash and cash equivalents include $3.21 million and $4.44 million at September 30, 2013 and December 31, 2012, respectively, of cash primarily pertaining to oil and gas revenue payments. There were corresponding accounts payable recorded at September 30, 2013 and December 31, 2012 for these liabilities. Both the restricted cash and the accounts payable are classified as current on the accompanying condensed consolidated balance sheets.

Additional_Balance_Sheet_Infor

Additional Balance Sheet Information	9 Months Ended
	Sep. 30, 2013
Text Block [Abstract]	'
Additional Balance Sheet Information	'
	(4) Additional Balance Sheet Information:
	Certain balance sheet amounts are comprised of the following:
	(Thousands of dollars)	September 30,			December 31,
		2013			2012
	Accounts Receivable:
	Joint interest billing	$	3,777		$	2,189
	Trade receivables		2,574			1,580
	Oil and gas sales		11,472			9,362
	Other		232			436
			18,055			13,567
	Less: Allowance for doubtful accounts		(333	)		(355	)
	Total	$	17,722		$	13,212
	Accounts Payable:
	Trade	$	1,398		$	3,968
	Royalty and other owners		9,393			9,652
	Prepaid drilling deposits		693			306
	Other		6,315			5,642
	Total	$	17,799		$	19,568
	Accrued Liabilities:
	Compensation and related expenses	$	5,230		$	2,517
	Property costs		2,060			4,549
	Other		841			552
	Total	$	8,131		$	7,618

Property_and_Equipment

Property and Equipment	9 Months Ended
	Sep. 30, 2013
Property Plant And Equipment [Abstract]	'
Property and Equipment	'
	(5) Property and Equipment:
	Property and equipment at September 30, 2013 and December 31, 2012 consisted of the following:
	(Thousands of dollars)	September 30,			December 31,
		2013			2012
	Proved oil and gas properties, at cost	$	354,877		$	338,204
	Less: Accumulated depletion and depreciation		(164,414	)		(150,276	)
	Oil and Gas Properties, Net	$	190,463		$	187,928
	Field and office equipment	$	26,799		$	23,974
	Less: Accumulated depreciation		(15,807	)		(15,052	)
	Field and Office Equipment, Net	$	10,992		$	8,922
	Total Property and Equipment, Net	$	201,455		$	196,850

LongTerm_Bank_Debt

Long-Term Bank Debt	9 Months Ended
	Sep. 30, 2013
Debt Disclosure [Abstract]	'
Long-Term Bank Debt	'
	(6) Long-Term Bank Debt:
	Bank Debt:
	Effective July 30, 2010 the Company entered into a Second Amended and Restated Credit Agreement between Compass Bank as agent and a syndicated group of lenders (“Credit Agreement”). The Credit Agreement has a revolving line of credit and letter of credit facility of up to $250 million with a final maturity date of July 30, 2017. The credit facility is secured by substantially all of the Company’s oil and gas properties. The credit facility is subject to a borrowing base determined by the lenders taking into consideration the estimated value of PEC’s oil and gas properties in accordance with the lenders’ customary practices for oil and gas loans. This process involves reviewing PEC’s estimated proved reserves and their valuation. The borrowing base is redetermined semi-annually, and the available borrowing amount could be increased or decreased as a result of such redetermination. In addition, PEC and the lenders each have at their discretion the right to request the borrowing base be redetermined with a maximum of one such request each year. A revision to PEC’s reserves may prompt such a request on the part of the lenders, which could possibly result in a reduction in the borrowing base and availability under the credit facility. At any time if the sum of the outstanding borrowings and letter of credit exposures exceed the applicable portion of the borrowing base, PEC would be required to repay the excess amount within a prescribed period.
	At September 30, 2013, the credit facility borrowing base was $145.0 million with no required monthly reduction amount. The borrowings made within the credit facility may be placed in a base rate loan or LIBO rate loan. The Company’s borrowing rates in the credit facility provide for base rate loans at the prime rate (3.25% at September 30, 2013) plus applicable margin utilization rates that range from 1.75% to 2.00%, and LIBO rate loans at LIBO published rates plus applicable utilization rates (2.75% to 3.00% at September 30, 2013). At September 30, 2013, the Company had in place one base rate loan and one LIBO rate loan with effective rates of 5.00% and 2.95%, respectively.
	At September 30, 2013, the Company had a total of $107.0 million of borrowings outstanding under its revolving credit facility at a weighted-average interest rate of 3.48% and $38.0 million available for future borrowings. The combined weighted average interest rate paid on outstanding bank borrowings subject to base rate and LIBO interest was 3.53% for the nine months ended September 30, 2013 as compared to 3.80% for the nine months ended September 30, 2012.
	On July 31, 2013, the Company entered into a $10.0 million Loan and Security Agreement with JP Morgan Chase Bank (“Equipment Loan”). The Equipment Loan is secured by substantially all of the Company’s field service equipment, carries an interest rate of 3.95% per annum, requires monthly payments (principal and interest) of $184,000, and has a final maturity date of July 31, 2018. As of September 30, 2013, the Company had a total of $9.8 million outstanding on the Equipment Loan
	The Company has entered into interest rate hedge agreements to help manage interest rate exposure. These contracts include interest rate swaps. Interest rate swap transactions generally involve the exchange of fixed and floating rate interest payment obligations without the exchange of the underlying principal amounts. In July 2012, the Company entered into interest swap agreements for a period of two years, which commence in January 2014, related to $75 million of the Company’s bank debt resulting in a fixed rate of 0.563% plus the Company’s current applicable margin.

Other_LongTerm_Obligations_and

Other Long-Term Obligations and Commitments	9 Months Ended
	Sep. 30, 2013
Text Block [Abstract]	'
Other Long-Term Obligations and Commitments	'
	(7) Other Long-Term Obligations and Commitments:
	Operating Leases:
	The Company has several non-cancelable operating leases, primarily for rental of office space, that have a term of more than one year. The future minimum lease payments for the rest of fiscal 2013 and thereafter for the operating leases are as follows:
	(Thousands of dollars)	Operating
		Leases
	2013	$	166
	2014		689
	2015		588
	2016		482
	2017		40
	Total minimum payments	$	1,965
	Rent expense for office space for the nine months ended September 30, 2013 and 2012 was $548,000 and $581,000, respectively.
	Asset Retirement Obligation:
	A reconciliation of the liability for plugging and abandonment costs for the nine months ended September 30, 2013 is as follows:
	(Thousands of dollars)
	Asset retirement obligation – December 31, 2012	$	9,012
	Liabilities incurred		165
	Liabilities settled		(811	)
	Accretion expense		283
	Revisions in estimated liabilities		1,791
	Asset retirement obligation – September 30, 2013	$	10,440
	The Company’s liability is determined using significant assumptions, including current estimates of plugging and abandonment costs, annual inflation of these costs, the productive life of wells and a risk-adjusted interest rate. Changes in any of these assumptions can result in significant revisions to the estimated asset retirement obligation. Revisions to the asset retirement obligation are recorded with an offsetting change to producing properties, resulting in prospective changes to depreciation, depletion and amortization expense and accretion of discount. Because of the subjectivity of assumptions and the relatively long life of most of the Company’s wells, the costs to ultimately retire the wells may vary significantly from previous estimates.

Contingent_Liabilities

Contingent Liabilities	9 Months Ended
	Sep. 30, 2013
Commitments And Contingencies Disclosure [Abstract]	'
Contingent Liabilities	'
	(8) Contingent Liabilities:
	The Company, as managing general partner of the affiliated Partnerships, is responsible for all Partnership activities, including the drilling of development wells and the production and sale of oil and gas from productive wells. The Company also provides the administration, accounting and tax preparation work for the Partnerships, and is liable for all debts and liabilities of the affiliated Partnerships, to the extent that the assets of a given limited Partnership are not sufficient to satisfy its obligations. As of September 30, 2013, the affiliated Partnerships have established cash reserves in excess of their debts and liabilities and the Company believes these reserves will be sufficient to satisfy Partnership obligations.
	The Company is subject to environmental laws and regulations. Management believes that future expenses, before recoveries from third parties, if any, will not have a material effect on the Company’s financial condition. This opinion is based on expenses incurred to date for remediation and compliance with laws and regulations, which have not been material to the Company’s results of operations.
	From time to time, the Company is party to certain legal actions arising in the ordinary course of business. While the outcome of these events cannot be predicted with certainty, management does not expect these matters to have a materially adverse effect on the financial position or results of operations of the Company.

Stock_Options_and_Other_Compen

Stock Options and Other Compensation	9 Months Ended
	Sep. 30, 2013
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]	'
Stock Options and Other Compensation	'
	(9) Stock Options and Other Compensation:
	In May 1989, non-statutory stock options were granted by the Company to four key executive officers for the purchase of shares of common stock. At September 30, 2013 and 2012, remaining options held by two key executive officers on 767,500 shares were outstanding and exercisable at prices ranging from $1.00 to $1.25. According to their terms, the options have no expiration date.

Related_Party_Transactions

Related Party Transactions	9 Months Ended
	Sep. 30, 2013
Related Party Transactions [Abstract]	'
Related Party Transactions	'
	(10) Related Party Transactions:
	The Company, as managing general partner or managing trustee, makes an annual offer to repurchase the interests of the partners and trust unit holders in certain of the Partnerships or Trusts. The Company purchased such interests in amounts totaling $14,000 and $66,000 for the nine months ended September 30, 2013 and 2012, respectively.
	Treasury stock purchases in any reported period may include shares from a related party, which may include members of the Company’s Board of Directors.
	Receivables from related parties consist of reimbursable general and administrative costs, lease operating expenses and reimbursement for property development and related costs. These receivables are due from joint venture partners, which may include members of the Company’s Board of Directors.
	Payables owed to related parties primarily represent receipts collected by the Company as agent for the joint venture partners, which may include members of the Company’s Board of Directors, for oil and gas sales net of expenses.

Financial_Instruments

Financial Instruments	9 Months Ended
	Sep. 30, 2013
Fair Value Disclosures [Abstract]	'
Financial Instruments	'
	(11) Financial Instruments:
	Fair Value Measurements:
	Authoritative guidance on fair value measurements defines fair value, establishes a framework for measuring fair value and stipulates the related disclosure requirements. The Company follows a three-level hierarchy, prioritizing and defining the types of inputs used to measure fair value. The fair values of the Company’s interest rate swaps, natural gas and crude oil price collars and swaps are designated as Level 3. The following fair value hierarchy table presents information about the Company’s assets and liabilities measured at fair value on a recurring basis as of September 30, 2013 and December 31, 2012:
	September 30, 2013		Quoted Prices in				Significant				Significant			Balance as of
			Active Markets				Other				Unobservable			September 30,
			For Identical				Observable
	(Thousands of dollars)		Assets (Level 1)				Inputs (Level 2)				Inputs (Level 3)			2013
	Assets
	Commodity derivative contracts		$	—			$	—			$	1,251		$	1,251
	Interest rate derivative contracts			—				—				135			135
	Total assets		$	—			$	—			$	1,386		$	1,386
	Liabilities
	Commodity derivative contracts		$	—			$	—			$	(2,747	)	$	(2,747	)
	Interest rate derivative contracts			—				—				(222	)		(222	)
	Total liabilities		$	—			$	—			$	(2,969	)	$	(2,969	)
	December 31, 2012		Quoted Prices in				Significant				Significant			Balance as of
			Active Markets				Other				Unobservable			December 31,
			For Identical				Observable
	(Thousands of dollars)		Assets (Level 1)				Inputs (Level 2)				Inputs (Level 3)			2012
	Assets
	Commodity derivative contracts		$	—			$	—			$	1,347		$	1,347
	Total assets		$	—			$	—			$	1,347		$	1,347
	Liabilities
	Commodity derivative contracts		$	—			$	—			$	(1,371	)	$	(1,371	)
	Interest rate derivative contracts			—				—				(54	)		(54	)
	Total liabilities		$	—			$	—			$	(1,425	)	$	(1,425	)
	The derivative contracts were measured based on quotes from the Company’s counterparties. Such quotes have been derived using valuation models that consider various inputs including current market and contractual prices for the underlying instruments, quoted forward prices for natural gas and crude oil, volatility factors and interest rates, such as a LIBOR curve for a similar length of time as the derivative contract term as applicable. These estimates are verified using comparable NYMEX futures contracts or are compared to multiple quotes obtained from counterparties for reasonableness.
	The significant unobservable inputs for Level 3 derivative contracts include basis differentials and volatility factors. An increase (decrease) in these unobservable inputs would result in an increase (decrease) in fair value, respectively. The Company does not have access to the specific assumptions used in its counterparties’ valuation models. Consequently, additional disclosures regarding significant Level 3 unobservable inputs were not provided.
	The following table sets forth a reconciliation of changes in the fair value of financial assets and liabilities classified as Level 3 in the fair value hierarchy for the nine months ended September 30, 2013.
	(Thousands of dollars)
	Net liabilities – December 31, 2012		$	(78	)
	Total realized and unrealized gains / losses:
	Included in earnings (a)			(2,599	)
	Included in other comprehensive gain			(33	)
	Purchases, sales, issuances and settlements			1,127
	Net liabilities – September 30, 2013		$	(1,583	)
	(a)	Derivative instruments are reported in revenues as realized gain/loss and on a separately reported line item captioned unrealized gain/loss on derivative instruments, and interest rate swap instruments are reported as a reduction to interest expense.
	Derivative Instruments:
	The Company is exposed to commodity price and interest rate risk, and management considers periodically the Company’s exposure to cash flow variability resulting from the commodity price changes and interest rate fluctuations. Futures, swaps and options are used to manage the Company’s exposure to commodity price risk inherent in the Company’s oil and gas production operations. The Company does not apply hedge accounting to any of its commodity based derivatives. Both realized and unrealized gains and losses associated with derivative instruments are recognized in earnings.
	Interest rate swap derivatives are treated as cash-flow hedges and are used to fix or float interest rates on existing debt. The value of these interest rate swaps at September 30, 2013 and December 31, 2012 is located in accumulated other comprehensive income (loss), net of tax. Settlement of the swaps, currently scheduled to begin in January 2014, will be recorded within interest expense.
	The following table sets forth the effect of derivative instruments on the condensed consolidated balance sheets at September 30, 2013 and December 31, 2012:
					Fair Value
	(Thousands of dollars)		Balance Sheet Location		September 30,				December 31,
					2013				2012
	Asset Derivatives:
	Derivatives designated as cash-flow hedging instruments:
	Interest rate swap contracts		Other assets		$	135			$	—
	Derivatives not designated as cash-flow hedging instruments:
	Crude oil commodity contracts		Other current assets			—				189
	Natural gas commodity contracts		Other current assets			523				1,040
	Crude oil commodity contracts		Other assets			703				118
	Natural gas commodity contracts		Other assets			25				—
	Total				$	1,386			$	1,347
	Liability Derivatives:
	Derivatives designated as cash-flow hedging instruments:
	Interest rate swap contracts		Derivative liability short-term		$	(158	)		$	—
	Interest rate swap contracts		Derivative liability long-term			(64	)			(54	)
	Derivatives not designated as cash-flow hedging instruments:
	Crude oil commodity contracts		Derivative liability short-term			(2,598	)			(994	)
	Natural gas commodity contracts		Derivative liability short-term			(4	)			—
	Crude oil commodity contracts		Derivative liability long-term			(145	)			(377	)
	Total				$	(2,969	)		$	(1,425	)
	Total derivative instruments				$	(1,583	)		$	(78	)
The following table sets forth the offsetting of asset and liability derivatives in the condensed consolidated balance sheets at September 30, 2013 and December 31, 2012:
(Thousands of dollars)		September 30,				December 31,
		2013				2012
Asset Derivatives:
Gross amount of recognized assets		$	2,342			$	4,209
Gross amounts offset in the balance sheet			(956	)			(2,862	)
Net amount		$	1,386			$	1,347
Liability Derivatives:
Gross amount of recognized liabilities		$	(3,925	)		$	(4,287	)
Gross amounts offset in the balance sheet			956				2,862
Net amount		$	(2,969	)		$	(1,425	)
Total derivative instruments		$	(1,583	)		$	(78	)
The following table sets forth the effect of derivative instruments on the condensed consolidated statements of operations for the nine months ended September 30, 2013 and 2012:
		Location of gain/loss recognized		Amount of gain/loss
		in income		recognized in income
(Thousands of dollars)				2013				2012
Derivatives not designated as cash-flow hedge instruments
Natural gas commodity contracts		Unrealized loss on derivative instruments, net		$	(495	)		$	—
Crude oil commodity contracts		Unrealized gain (loss) on derivative instruments, net			(977	)			2,449
Natural gas commodity contracts		Realized gain on derivative instruments, net			571				—
Crude oil commodity contracts (a)		Realized gain (loss) on derivative instruments, net			(1,698	)			379
				$	(2,599	)		$	2,828
(a)	During the nine months ended September 30, 2012, the Company unwound and monetized crude oil swaps with original settlement dates from January 2012 through December 2013 for net proceeds of $1,030,000. The $1,030,000 gain associated with these early settlement transactions is included in realized gain on derivative instruments for the nine months ended September 30, 2012.

Earnings_Per_Share

Earnings Per Share	9 Months Ended
	Sep. 30, 2013
Earnings Per Share [Abstract]	'
Earnings Per Share	'
	(12) Earnings Per Share:
	Basic earnings per share are computed by dividing earnings available to common stockholders by the weighted average number of common shares outstanding during the period. Diluted earnings per share reflect per share amounts that would have resulted if dilutive potential common stock had been converted to common stock in gain periods. The following reconciles amounts reported in the financial statements:
		Nine Months Ended September 30,
		2013						2012
		Net Income		Weighted		Per Share		Net Income		Weighted		Per Share
		(In 000’s)		Average		Amount		(In 000’s)		Average		Amount
				Number of						Number of
				Shares						Shares
				Outstanding						Outstanding
	Basic	$	10,584		2,448,743	$	4.32	$	10,088		2,645,924	$	3.81
	Effect of dilutive securities:
	Options		—		743,966				—		734,680
	Diluted	$	10,584		3,192,709	$	3.32	$	10,088		3,380,604	$	2.98
		Three Months Ended September 30,
		2013						2012
		Net Income		Weighted		Per Share		Net Income		Weighted		Per Share
		(In 000’s)		Average		Amount		(In 000’s)		Average		Amount
				Number of						Number of
				Shares						Shares
				Outstanding						Outstanding
	Basic	$	2,232		2,415,303	$	0.92	$	1,342		2,608,319	$	0.51
	Effect of dilutive securities:
	Options		—		749,664				—		737,162
	Diluted	$	2,232		3,164,967	$	0.71	$	1,342		3,345,481	$	0.4

Basis_of_Presentation_Policies

Basis of Presentation (Policies)	9 Months Ended
	Sep. 30, 2013
Accounting Policies [Abstract]	'
Recently Issued Accounting Pronouncements	'
	Recently Issued Accounting Pronouncements
	In December 2011, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2011-11, “Disclosures about Offsetting Assets and Liabilities.” This ASU requires enhanced disclosures including both gross and net information about financial and derivative instruments eligible for offset or subject to an enforceable master netting arrangement or similar agreement. This new guidance is effective for annual reporting periods beginning on or after January 1, 2013 and subsequent interim periods. In January 2013, the FASB issued ASU 2013-01, “Clarifying the Scope of Disclosures about Offsetting Assets and Liabilities.” ASU 2013-01 clarifies the scope of ASU 2011-11 to apply to derivative instruments that are offset or subject to an enforceable master netting arrangement or similar agreement. This clarified guidance is effective for annual reporting periods beginning on or after January 1, 2013 and subsequent interim periods. The revised requirements of ASU 2011-11 and ASU 2013-01 impacted the disclosures associated with the Company’s derivative instruments (Note 11) and did not have a material impact on the Company’s condensed consolidated financial position, results of operations or cash flows.
	In February 2013, the FASB issued ASU 2013-02, “Reporting of Amounts Reclassified Out of Accumulated Other Comprehensive Income” (“AOCI”). ASU 2013-02 requires a rollforward of changes in AOCI by component and information about significant reclassifications from AOCI to net earnings to be presented in one location, either on the face of the financial statements or in the notes. This new guidance is effective for fiscal years beginning after December 15, 2012 and subsequent interim periods. The revised disclosure requirements of ASU 2013-02 are reflected in Note 11. The requirements of ASU 2013-02 did not have a material impact on the Company’s condensed consolidated financial position, results of operations or cash flows.

Additional_Balance_Sheet_Infor1

Additional Balance Sheet Information (Tables)	9 Months Ended
	Sep. 30, 2013
Text Block [Abstract]	'
Components of Balance Sheet Amounts	'
	Certain balance sheet amounts are comprised of the following:
	(Thousands of dollars)	September 30,			December 31,
		2013			2012
	Accounts Receivable:
	Joint interest billing	$	3,777		$	2,189
	Trade receivables		2,574			1,580
	Oil and gas sales		11,472			9,362
	Other		232			436
			18,055			13,567
	Less: Allowance for doubtful accounts		(333	)		(355	)
	Total	$	17,722		$	13,212
	Accounts Payable:
	Trade	$	1,398		$	3,968
	Royalty and other owners		9,393			9,652
	Prepaid drilling deposits		693			306
	Other		6,315			5,642
	Total	$	17,799		$	19,568
	Accrued Liabilities:
	Compensation and related expenses	$	5,230		$	2,517
	Property costs		2,060			4,549
	Other		841			552
	Total	$	8,131		$	7,618

Property_and_Equipment_Tables

Property and Equipment (Tables)	9 Months Ended
	Sep. 30, 2013
Property Plant And Equipment [Abstract]	'
Components of Property and Equipment	'
	Property and equipment at September 30, 2013 and December 31, 2012 consisted of the following:
	(Thousands of dollars)	September 30,			December 31,
		2013			2012
	Proved oil and gas properties, at cost	$	354,877		$	338,204
	Less: Accumulated depletion and depreciation		(164,414	)		(150,276	)
	Oil and Gas Properties, Net	$	190,463		$	187,928
	Field and office equipment	$	26,799		$	23,974
	Less: Accumulated depreciation		(15,807	)		(15,052	)
	Field and Office Equipment, Net	$	10,992		$	8,922
	Total Property and Equipment, Net	$	201,455		$	196,850

Other_LongTerm_Obligations_and1

Other Long-Term Obligations and Commitments (Tables)	9 Months Ended
	Sep. 30, 2013
Text Block [Abstract]	'
Summary of Future Minimum Lease Payments for Non-Cancelable Operating Leases	'
	The future minimum lease payments for the rest of fiscal 2013 and thereafter for the operating leases are as follows:
	(Thousands of dollars)	Operating
		Leases
	2013	$	166
	2014		689
	2015		588
	2016		482
	2017		40
	Total minimum payments	$	1,965
Reconciliation of Liability for Plugging and Abandonment Costs	'
	A reconciliation of the liability for plugging and abandonment costs for the nine months ended September 30, 2013 is as follows:
	(Thousands of dollars)
	Asset retirement obligation – December 31, 2012	$	9,012
	Liabilities incurred		165
	Liabilities settled		(811	)
	Accretion expense		283
	Revisions in estimated liabilities		1,791
	Asset retirement obligation – September 30, 2013	$	10,440

Financial_Instruments_Tables

Financial Instruments (Tables)	9 Months Ended
	Sep. 30, 2013
Fair Value Disclosures [Abstract]	'
Schedule of Assets and Liabilities Measured at Fair Value on a Recurring Basis	'
	The following fair value hierarchy table presents information about the Company’s assets and liabilities measured at fair value on a recurring basis as of September 30, 2013 and December 31, 2012:
	September 30, 2013		Quoted Prices in				Significant				Significant			Balance as of
			Active Markets				Other				Unobservable			September 30,
			For Identical				Observable
	(Thousands of dollars)		Assets (Level 1)				Inputs (Level 2)				Inputs (Level 3)			2013
	Assets
	Commodity derivative contracts		$	—			$	—			$	1,251		$	1,251
	Interest rate derivative contracts			—				—				135			135
	Total assets		$	—			$	—			$	1,386		$	1,386
	Liabilities
	Commodity derivative contracts		$	—			$	—			$	(2,747	)	$	(2,747	)
	Interest rate derivative contracts			—				—				(222	)		(222	)
	Total liabilities		$	—			$	—			$	(2,969	)	$	(2,969	)
	December 31, 2012		Quoted Prices in				Significant				Significant			Balance as of
			Active Markets				Other				Unobservable			December 31,
			For Identical				Observable
	(Thousands of dollars)		Assets (Level 1)				Inputs (Level 2)				Inputs (Level 3)			2012
	Assets
	Commodity derivative contracts		$	—			$	—			$	1,347		$	1,347
	Total assets		$	—			$	—			$	1,347		$	1,347
	Liabilities
	Commodity derivative contracts		$	—			$	—			$	(1,371	)	$	(1,371	)
	Interest rate derivative contracts			—				—				(54	)		(54	)
	Total liabilities		$	—			$	—			$	(1,425	)	$	(1,425	)
Schedule of Changes in Fair Value of Financial Assets and Liabilities Classified as Level 3	'
	The following table sets forth a reconciliation of changes in the fair value of financial assets and liabilities classified as Level 3 in the fair value hierarchy for the nine months ended September 30, 2013.
	(Thousands of dollars)
	Net liabilities – December 31, 2012		$	(78	)
	Total realized and unrealized gains / losses:
	Included in earnings (a)			(2,599	)
	Included in other comprehensive gain			(33	)
	Purchases, sales, issuances and settlements			1,127
	Net liabilities – September 30, 2013		$	(1,583	)
	(a)	Derivative instruments are reported in revenues as realized gain/loss and on a separately reported line item captioned unrealized gain/loss on derivative instruments, and interest rate swap instruments are reported as a reduction to interest expense.
Effect of Derivative Instruments on Condensed Consolidated Balance Sheets	'
	The following table sets forth the effect of derivative instruments on the condensed consolidated balance sheets at September 30, 2013 and December 31, 2012:
					Fair Value
	(Thousands of dollars)		Balance Sheet Location		September 30,				December 31,
					2013				2012
	Asset Derivatives:
	Derivatives designated as cash-flow hedging instruments:
	Interest rate swap contracts		Other assets		$	135			$	—
	Derivatives not designated as cash-flow hedging instruments:
	Crude oil commodity contracts		Other current assets			—				189
	Natural gas commodity contracts		Other current assets			523				1,040
	Crude oil commodity contracts		Other assets			703				118
	Natural gas commodity contracts		Other assets			25				—
	Total				$	1,386			$	1,347
	Liability Derivatives:
	Derivatives designated as cash-flow hedging instruments:
	Interest rate swap contracts		Derivative liability short-term		$	(158	)		$	—
	Interest rate swap contracts		Derivative liability long-term			(64	)			(54	)
	Derivatives not designated as cash-flow hedging instruments:
	Crude oil commodity contracts		Derivative liability short-term			(2,598	)			(994	)
	Natural gas commodity contracts		Derivative liability short-term			(4	)			—
	Crude oil commodity contracts		Derivative liability long-term			(145	)			(377	)
	Total				$	(2,969	)		$	(1,425	)
	Total derivative instruments				$	(1,583	)		$	(78	)
Schedule of Offsetting Asset and Liability Derivatives in the Condensed Consolidated Balance Sheets	'
	The following table sets forth the offsetting of asset and liability derivatives in the condensed consolidated balance sheets at September 30, 2013 and December 31, 2012:
	(Thousands of dollars)		September 30,				December 31,
			2013				2012
	Asset Derivatives:
	Gross amount of recognized assets		$	2,342			$	4,209
	Gross amounts offset in the balance sheet			(956	)			(2,862	)
	Net amount		$	1,386			$	1,347
	Liability Derivatives:
	Gross amount of recognized liabilities		$	(3,925	)		$	(4,287	)
	Gross amounts offset in the balance sheet			956				2,862
	Net amount		$	(2,969	)		$	(1,425	)
	Total derivative instruments		$	(1,583	)		$	(78	)
Effect of Derivative Instruments on Condensed Consolidated Statements of Operations	'
	The following table sets forth the effect of derivative instruments on the condensed consolidated statements of operations for the nine months ended September 30, 2013 and 2012:
			Location of gain/loss recognized		Amount of gain/loss
			in income		recognized in income
	(Thousands of dollars)				2013				2012
	Derivatives not designated as cash-flow hedge instruments
	Natural gas commodity contracts		Unrealized loss on derivative instruments, net		$	(495	)		$	—
	Crude oil commodity contracts		Unrealized gain (loss) on derivative instruments, net			(977	)			2,449
	Natural gas commodity contracts		Realized gain on derivative instruments, net			571				—
	Crude oil commodity contracts (a)		Realized gain (loss) on derivative instruments, net			(1,698	)			379
					$	(2,599	)		$	2,828
	(a)	During the nine months ended September 30, 2012, the Company unwound and monetized crude oil swaps with original settlement dates from January 2012 through December 2013 for net proceeds of $1,030,000. The $1,030,000 gain associated with these early settlement transactions is included in realized gain on derivative instruments for the nine months ended September 30, 2012.

Earnings_Per_Share_Tables

Earnings Per Share (Tables)	9 Months Ended
	Sep. 30, 2013
Earnings Per Share [Abstract]	'
Computation of Basic and Diluted Earnings (Loss) Per Share	'
	The following reconciles amounts reported in the financial statements:
		Nine Months Ended September 30,
		2013						2012
		Net Income		Weighted		Per Share		Net Income		Weighted		Per Share
		(In 000’s)		Average		Amount		(In 000’s)		Average		Amount
				Number of						Number of
				Shares						Shares
				Outstanding						Outstanding
	Basic	$	10,584		2,448,743	$	4.32	$	10,088		2,645,924	$	3.81
	Effect of dilutive securities:
	Options		—		743,966				—		734,680
	Diluted	$	10,584		3,192,709	$	3.32	$	10,088		3,380,604	$	2.98
		Three Months Ended September 30,
		2013						2012
		Net Income		Weighted		Per Share		Net Income		Weighted		Per Share
		(In 000’s)		Average		Amount		(In 000’s)		Average		Amount
				Number of						Number of
				Shares						Shares
				Outstanding						Outstanding
	Basic	$	2,232		2,415,303	$	0.92	$	1,342		2,608,319	$	0.51
	Effect of dilutive securities:
	Options		—		749,664				—		737,162
	Diluted	$	2,232		3,164,967	$	0.71	$	1,342		3,345,481	$	0.4

Acquisitions_and_Dispositions_

Acquisitions and Dispositions - Additional Information (Detail) (USD $)	9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012
	Trust
	Investment
Business Combinations [Abstract]	'	'
Number of limited partnerships	18	'
Number of business income trusts	2	'
Purchase of non-controlling interests	$14,000	$66,000

Restricted_Cash_and_Cash_Equiv1

Restricted Cash and Cash Equivalents - Additional Information (Detail) (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Millions, unless otherwise specified
Cash And Cash Equivalents [Abstract]	'	'
Restricted cash and cash equivalents pertaining to oil and gas revenue payments	$3.21	$4.44

Additional_Balance_Sheet_Infor2

Additional Balance Sheet Information - Components of Balance Sheet Amounts (Detail) (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Accounts Receivable:	'	'
Joint interest billing	$3,777	$2,189
Trade receivables	2,574	1,580
Oil and gas sales	11,472	9,362
Other	232	436
Accounts Receivable, Gross	18,055	13,567
Less: Allowance for doubtful accounts	-333	-355
Total	17,722	13,212
Accounts Payable:	'	'
Trade	1,398	3,968
Royalty and other owners	9,393	9,652
Prepaid drilling deposits	693	306
Other	6,315	5,642
Total	17,799	19,568
Accrued Liabilities:	'	'
Compensation and related expenses	5,230	2,517
Property costs	2,060	4,549
Other	841	552
Total	$8,131	$7,618

Property_and_Equipment_Compone

Property and Equipment - Components of Property and Equipment (Detail) (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Property Plant And Equipment [Abstract]	'	'
Proved oil and gas properties, at cost	$354,877	$338,204
Less: Accumulated depletion and depreciation	-164,414	-150,276
Oil and Gas Properties, Net	190,463	187,928
Field and office equipment	26,799	23,974
Less: Accumulated depreciation	-15,807	-15,052
Field and Office Equipment, Net	10,992	8,922
Total Property and Equipment, Net	$201,455	$196,850

LongTerm_Bank_Debt_Additional_

Long-Term Bank Debt - Additional Information (Detail) (USD $)	9 Months Ended					9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Jul. 31, 2013	Sep. 30, 2013	Sep. 30, 2013	Sep. 30, 2013
			Equipment Loan [Member]	Equipment Loan [Member]	Interest rate swap [Member]	Minimum [Member]	Maximum [Member]
Debt Instrument [Line Items]	'	'	'	'	'	'	'
Credit facility borrowing capacity	$250,000,000	'	'	'	'	'	'
Maturity date of amended and restated credit agreement	30-Jul-17	'	'	'	'	'	'
Credit facility borrowing base	145,000,000	'	'	'	'	'	'
Credit facility, interest rate description	'The Company's borrowing rates in the credit facility provide for base rate loans at the prime rate (3.25% at September 30, 2013) plus applicable margin utilization rates that range from 1.75% to 2.00%, and LIBO rate loans at LIBO published rates plus applicable utilization rates (2.75% to 3.00% at September 30, 2013). At September 30, 2013, the Company had in place one base rate loan and one LIBO rate loan with effective rates of 5.00% and 2.95%, respectively.	'	'	'	'	'	'
Percentage for base rate loans at the prime rate	3.25%	'	3.95%	'	0.56%	'	'
Minimum range for applicable margin utilization rate	1.75%	'	'	'	'	'	'
Maximum range for applicable margin utilization rate	2.00%	'	'	'	'	'	'
Debt instrument interest one base rate basis for effective rate	5.00%	'	'	'	'	'	'
LIBOR rate loans	'	'	'	'	'	2.75%	3.00%
Effective LIBOR loan rate	2.95%	'	'	'	'	'	'
Outstanding borrowings under revolving credit facility	107,000,000	'	'	'	'	'	'
Weighted-average interest rate of borrowings	3.48%	'	'	'	'	'	'
Credit facility remaining borrowing capacity	38,000,000	'	'	'	'	'	'
Debt instrument basis weighted average interest rate spread on variable rate	3.53%	3.80%	'	'	'	'	'
Equipment Loan, face amount	'	'	'	10,000,000	'	'	'
Equipment Loan, monthly payment	'	'	184,000	'	'	'	'
Equipment Loan, maturity date	'	'	31-Jul-18	'	'	'	'
Company's bank debt	'	'	$9,800,000	'	$75,000,000	'	'
Interest swap agreements period	'2 years	'	'	'	'	'	'

Other_LongTerm_Obligations_and2

Other Long-Term Obligations and Commitments - Additional Information (Detail) (USD $)	9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012
Commitments And Contingencies Disclosure [Abstract]	'	'
Lease period description	'Term of more than one year	'
Rent expense for office space	$548,000	$581,000

Other_LongTerm_Obligations_and3

Other Long-Term Obligations and Commitments - Summary of Future Minimum Lease Payments for Non-Cancelable Operating Leases (Detail) (USD $)	Sep. 30, 2013
In Thousands, unless otherwise specified
Commitments And Contingencies Disclosure [Abstract]	'
2013	$166
2014	689
2015	588
2016	482
2017	40
Total minimum payments	$1,965

Other_LongTerm_Obligations_and4

Other Long-Term Obligations and Commitments - Reconciliation of Liability for Plugging and Abandonment Costs (Detail) (USD $)	9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013
Commitments And Contingencies Disclosure [Abstract]	'
Asset retirement obligation - December 31, 2012	$9,012
Liabilities incurred	165
Liabilities settled	-811
Accretion expense	283
Revisions in estimated liabilities	1,791
Asset retirement obligation - September 30, 2013	$10,440

Stock_Options_and_Other_Compen1

Stock Options and Other Compensation - Additional Information (Detail) (USD $)	Sep. 30, 2013	Sep. 30, 2012	31-May-89
	Officers	Officers	Officers
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'
Options outstanding, shares	767,500	767,500	'
Option exercisable, shares	767,500	767,500	'
Number of key executive officers who held remaining options outstanding and exercisable	2	2	'
Number of key executive officers to whom non-statutory stock options granted	'	'	4
Minimum [Member]	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'
Average exercise price	1	1	'
Maximum [Member]	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'
Average exercise price	1.25	1.25	'

Related_Party_Transactions_Add

Related Party Transactions - Additional Information (Detail) (USD $)	9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012
Related Party Transactions [Abstract]	'	'
Repurchase interests of partners and trust unit holders	$14,000	$66,000

Financial_Instruments_Schedule

Financial Instruments - Schedule of Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Assets	'	'
Derivative assets	$1,386	$1,347
Liabilities	'	'
Derivative liabilities	-2,969	-1,425
Fair Value, Measurements, Recurring [Member]	'	'
Assets	'	'
Derivative assets	1,386	1,347
Liabilities	'	'
Derivative liabilities	-2,969	-1,425
Commodity derivative contracts [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Assets	'	'
Derivative assets	1,251	1,347
Liabilities	'	'
Derivative liabilities	-2,747	-1,371
Interest rate derivative contracts [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Assets	'	'
Derivative assets	135	'
Liabilities	'	'
Derivative liabilities	-222	-54
Quoted Prices in Active Markets For Identical Assets (Level 1) [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Assets	'	'
Derivative assets	'	'
Liabilities	'	'
Derivative liabilities	'	'
Quoted Prices in Active Markets For Identical Assets (Level 1) [Member] | Commodity derivative contracts [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Assets	'	'
Derivative assets	'	'
Liabilities	'	'
Derivative liabilities	'	'
Quoted Prices in Active Markets For Identical Assets (Level 1) [Member] | Interest rate derivative contracts [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Assets	'	'
Derivative assets	'	'
Liabilities	'	'
Derivative liabilities	'	'
Significant Other Observable Inputs (Level 2) [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Assets	'	'
Derivative assets	'	'
Liabilities	'	'
Derivative liabilities	'	'
Significant Other Observable Inputs (Level 2) [Member] | Commodity derivative contracts [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Assets	'	'
Derivative assets	'	'
Liabilities	'	'
Derivative liabilities	'	'
Significant Other Observable Inputs (Level 2) [Member] | Interest rate derivative contracts [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Assets	'	'
Derivative assets	'	'
Liabilities	'	'
Derivative liabilities	'	'
Significant Unobservable Inputs (Level 3) [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Assets	'	'
Derivative assets	1,386	1,347
Liabilities	'	'
Derivative liabilities	-2,969	-1,425
Significant Unobservable Inputs (Level 3) [Member] | Commodity derivative contracts [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Assets	'	'
Derivative assets	1,251	1,347
Liabilities	'	'
Derivative liabilities	-2,747	-1,371
Significant Unobservable Inputs (Level 3) [Member] | Interest rate derivative contracts [Member] | Fair Value, Measurements, Recurring [Member]	'	'
Assets	'	'
Derivative assets	135	'
Liabilities	'	'
Derivative liabilities	($222)	($54)

Financial_Instruments_Schedule1

Financial Instruments - Schedule of Changes in Fair Value of Financial Assets and Liabilities Classified as Level 3 (Detail) (Significant Unobservable Inputs (Level 3) [Member], USD $)	9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013
Significant Unobservable Inputs (Level 3) [Member]	'
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]	'
Net liabilities at beginning of period	($78)
Total realized and unrealized gains / losses	'
Included in earnings	-2,599
Included in other comprehensive gain	-33
Purchases, sales, issuances and settlements	1,127
Net liabilities at end of period	($1,583)

Financial_Instruments_Effect_o

Financial Instruments - Effect of Derivative Instruments on Condensed Consolidated Balance Sheets (Detail) (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Derivatives, Fair Value [Line Items]	'	'
Derivative assets	$1,386	$1,347
Derivative liabilities	-2,969	-1,425
Total derivative instruments	-1,583	-78
Other assets [Member] | Interest rate swap [Member] | Derivatives designated as cash-flow hedging instruments [Member]	'	'
Derivatives, Fair Value [Line Items]	'	'
Derivative assets	135	'
Other assets [Member] | Crude oil commodity contracts [Member] | Derivatives not designated as cash-flow hedging instruments [Member]	'	'
Derivatives, Fair Value [Line Items]	'	'
Derivative assets	703	118
Other assets [Member] | Natural gas commodity contracts [Member] | Derivatives not designated as cash-flow hedging instruments [Member]	'	'
Derivatives, Fair Value [Line Items]	'	'
Derivative assets	25	'
Other current assets [Member] | Crude oil commodity contracts [Member] | Derivatives not designated as cash-flow hedging instruments [Member]	'	'
Derivatives, Fair Value [Line Items]	'	'
Derivative assets	'	189
Other current assets [Member] | Natural gas commodity contracts [Member] | Derivatives not designated as cash-flow hedging instruments [Member]	'	'
Derivatives, Fair Value [Line Items]	'	'
Derivative assets	523	1,040
Derivative liability short-term [Member] | Interest rate swap [Member] | Derivatives designated as cash-flow hedging instruments [Member]	'	'
Derivatives, Fair Value [Line Items]	'	'
Derivative liabilities	-158	'
Derivative liability short-term [Member] | Crude oil commodity contracts [Member] | Derivatives not designated as cash-flow hedging instruments [Member]	'	'
Derivatives, Fair Value [Line Items]	'	'
Derivative liabilities	-2,598	-994
Derivative liability short-term [Member] | Natural gas commodity contracts [Member] | Derivatives not designated as cash-flow hedging instruments [Member]	'	'
Derivatives, Fair Value [Line Items]	'	'
Derivative liabilities	-4	'
Derivative liability long-term [Member] | Interest rate swap [Member] | Derivatives designated as cash-flow hedging instruments [Member]	'	'
Derivatives, Fair Value [Line Items]	'	'
Derivative liabilities	-64	-54
Derivative liability long-term [Member] | Crude oil commodity contracts [Member] | Derivatives not designated as cash-flow hedging instruments [Member]	'	'
Derivatives, Fair Value [Line Items]	'	'
Derivative liabilities	($145)	($377)

Financial_Instruments_Schedule2

Financial Instruments - Schedule of Offsetting Asset and Liability Derivatives in the Condensed Consolidated Balance Sheets (Detail) (USD $)	Sep. 30, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Asset Derivatives:	'	'
Gross amount of recognized assets	$2,342	$4,209
Gross amounts offset in the balance sheet	-956	-2,862
Net amount	1,386	1,347
Liability Derivatives:	'	'
Gross amount of recognized liabilities	-3,925	-4,287
Gross amounts offset in the balance sheet	956	2,862
Net amount	-2,969	-1,425
Total derivative instruments	($1,583)	($78)

Financial_Instruments_Effect_o1

Financial Instruments - Effect of Derivative Instruments on Condensed Consolidated Statements of Operations (Detail) (Derivatives not designated as cash-flow hedging instruments [Member], USD $)	9 Months Ended
In Thousands, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012
Derivatives not designated as cash-flow hedge instruments	'	'
Amount of gain/loss recognized in income	($2,599)	$2,828
Unrealized gain (loss) on derivative instruments, net [Member] | Natural gas commodity contracts [Member]	'	'
Derivatives not designated as cash-flow hedge instruments	'	'
Amount of gain/loss recognized in income	-495	'
Unrealized gain (loss) on derivative instruments, net [Member] | Crude oil commodity contracts [Member]	'	'
Derivatives not designated as cash-flow hedge instruments	'	'
Amount of gain/loss recognized in income	-977	2,449
Realized gain (loss) on derivative instruments, net [Member] | Natural gas commodity contracts [Member]	'	'
Derivatives not designated as cash-flow hedge instruments	'	'
Amount of gain/loss recognized in income	571	'
Realized gain (loss) on derivative instruments, net [Member] | Crude oil commodity contracts [Member]	'	'
Derivatives not designated as cash-flow hedge instruments	'	'
Amount of gain/loss recognized in income	($1,698)	$379

Financial_Instruments_Effect_o2

Financial Instruments - Effect of Derivative Instruments on Condensed Consolidated Statements of Operations (Parenthetical) (Detail) (USD $)	9 Months Ended
	Sep. 30, 2012
Fair Value Disclosures [Abstract]	'
Net proceeds from derivative instruments	$1,030,000

Earnings_Per_Share_Computation

Earnings Per Share - Computation of Basic and Diluted Earnings (Loss) Per Share (Detail) (USD $)	3 Months Ended		9 Months Ended
In Thousands, except Share data, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]	'	'	'	'
Net Income, Basic	$2,232	$1,342	$10,584	$10,088
Net Income, Diluted	$2,232	$1,342	$10,584	$10,088
Weighted Average Number of Shares Outstanding, Basic	2,415,303	2,608,319	2,448,743	2,645,924
Weighted Average Number of Shares Outstanding, Diluted	3,164,967	3,345,481	3,192,709	3,380,604
Net Income Per Share, Basic	$0.92	$0.51	$4.32	$3.81
Net Income Per Share, Diluted	$0.71	$0.40	$3.32	$2.98
Stock Options [Member]	'	'	'	'
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]	'	'	'	'
Effect of dilutive securities, Options	749,664	737,162	743,966	734,680