Oil and Gas Properties and Equipment, net (Notes)

12 Months Ended

Dec. 31, 2015

Oil and Gas Properties and Equipment, net

Net capitalized costs, utilizing the successful efforts method of accounting, related to our oil and gas producing activities are as follows:



	At Year-End
	2015			2014
	(In thousands)
Unproved leasehold interests	$	19,441		$	90,446
Proved oil and gas properties	119,414			221,299
Total costs	138,855			311,745
Less accumulated depreciation, depletion and amortization	(58,242		)	(48,252		)
	$	80,613		$	263,493

We review unproved oil and gas properties for impairment based on our current exploration plans and proved oil and gas properties by comparing the expected undiscounted future cash flows at a producing field level to the unamortized capitalized cost of the asset.

In 2015, we recognized $164,831,000 in non-cash impairment charges of which $107,140,000 related to our proved properties and $57,691,000 on our unproved leasehold interests principally due to a significant decline in oil prices, drilling results, a change in our plans to develop acreage and increased likelihood that non-core oil and gas assets will be sold. In 2014, we recognized $32,665,000 in non-cash impairment charges of which $17,130,000 related to our unproved leasehold interests and $15,535,000 on our proved properties principally due to the significant decline in oil prices, drilling results, a change in our plans to develop acreage and increased likelihood that non-core oil and gas assets will be sold. Impairment charges are included in cost of oil and gas producing activities on our consolidated statements of income (loss) and comprehensive income (loss).

In 2015, we recorded a net loss of $706,000 on the sale of 109,000 net mineral acres leased from others and the disposition of 39 gross (7 net) producing oil and gas wells in Nebraska, Texas, Colorado, North Dakota and Oklahoma for total sales proceeds of $17,800,000.