Asset Retirement Obligations

6 Months Ended

Jun. 30, 2016

Asset Retirement Obligation Disclosure [Abstract]

(9) ASSET RETIREMENT OBLIGATIONS

Our asset retirement obligations primarily represent the estimated present value of the amounts we will incur to plug, abandon and remediate our producing properties at the end of their productive lives. Significant inputs used in determining such obligations include estimates of plugging and abandonment costs, estimated future inflation rates and well lives. The inputs are calculated based on historical data as well as current estimated costs. A reconciliation of our liability for plugging and abandonment costs for the six months ended June 30, 2016 is as follows (in thousands):

	Six Months Ended June 30, 2016
Beginning of period	$	264,137
Liabilities incurred		921
Liabilities settled		(5,700	)
Disposition of wells		(4,731	)
Accretion expense		8,172
Change in estimate		2,819
End of period		265,618
Less current portion		(15,071	)
Long-term asset retirement obligations	$	250,547

Accretion expense is recognized as a component of depreciation, depletion and amortization expense in the accompanying consolidated statements of operations.