At December 31, 2018, we had in place ten commodity purchase and sale contracts with fair value associated with them as the contractual prices of crude oil were outside of the range of prices specified in the agreements. These commodity purchase and sale contracts encompassed approximately:

The estimated fair value of forward month commodity contracts (derivatives) reflected in the accompanying consolidated balance sheet were as follows at the date indicated (in thousands):


	December 31, 2018
	Balance Sheet Location and Amount
	Current		Other		Current		Other
	Assets		Assets		Liabilities		Liabilities
Asset derivatives:
Fair value forward hydrocarbon commodity
contracts at gross valuation	$	162	$	—	$	—	$	—
Liability derivatives:
Fair value forward hydrocarbon commodity
contracts at gross valuation	—		—		139		—
Less counterparty offsets	—		—		—		—
As reported fair value contracts	$	162	$	—	$	139	$	—

At December 31, 2017, we had in place twenty commodity purchase and sale contracts, of which four of these contracts had no fair value associated with them as the contractual prices of crude oil were within the range of prices specified in the agreements. These commodity purchase and sale contracts encompassed approximately:

The estimated fair value of forward month commodity contracts (derivatives) reflected in the accompanying consolidated balance sheet were as follows at the date indicated (in thousands):


	December 31, 2017
	Balance Sheet Location and Amount
	Current		Other		Current		Other
	Assets		Assets		Liabilities		Liabilities
Asset derivatives:
Fair value forward hydrocarbon commodity
contracts at gross valuation	$	166	$	—	$	—	$	—
Liability derivatives:
Fair value forward hydrocarbon commodity
contracts at gross valuation	—		—		145		—
Less counterparty offsets	—		—		—		—
As reported fair value contracts	$	166	$	—	$	145	$	—

We only enter into commodity contracts with creditworthy counterparties and evaluate our exposure to significant counterparties on an ongoing basis. At December 31, 2018 and 2017, we were not holding nor have we posted any collateral to support our forward month fair value derivative activity. We are not subject to any credit-risk related trigger events. We have no other financial investment arrangements that would serve to offset our derivative contracts.

Forward month commodity contracts (derivatives) reflected in the accompanying consolidated statements of operations were as follows for the periods indicated (in thousands):

The following tables set forth, by level with the Level 1, 2 and 3 fair value hierarchy, the carrying values of our financial assets and liabilities at the dates indicated (in thousands):


	December 31, 2018
	Fair Value Measurements Using
	Quoted Prices
	in Active		Significant
	Markets for		Other		Significant
	Identical Assets		Observable		Unobservable
	and Liabilities		Inputs		Inputs		Counterparty
	(Level 1)		(Level 2)		(Level 3)		Offsets		Total

Derivatives:
Current assets	$	—	$	162	$	—	$	—	$	162
Current liabilities	—		(139)		—		—		(139)
Net value	$	—	$	23	$	—	$	—	$	23


	December 31, 2017
	Fair Value Measurements Using
	Quoted Prices
	in Active		Significant
	Markets for		Other		Significant
	Identical Assets		Observable		Unobservable
	and Liabilities		Inputs		Inputs		Counterparty
	(Level 1)		(Level 2)		(Level 3)		Offsets		Total

Derivatives:
Current assets	$	—	$	166	$	—	$	—	$	166
Current liabilities	—		(145)		—		—		(145)
Net value	$	—	$	21	$	—	$	—	$	21

These assets and liabilities are measured on a recurring basis and are classified based on the lowest level of input used to estimate their fair value. Our assessment of the relative significance of these inputs requires judgments.

When determining fair value measurements, we make credit valuation adjustments to reflect both our own nonperformance risk and our counterparty’s nonperformance risk. When adjusting the fair value of derivative contracts for the effect of nonperformance risk, we consider the impact of netting and any applicable credit enhancements. Credit valuation adjustments utilize Level 3 inputs, such as credit scores to evaluate the likelihood of default by us or our counterparties. At December 31, 2018 and 2017, credit valuation adjustments were not significant to the overall valuation of our fair value contracts. As a result, applicable fair value assets and liabilities are included in their entirety in the fair value hierarchy.

Certain nonfinancial assets and liabilities are measured at fair value on a nonrecurring basis and are subject to fair value adjustments in certain circumstances, such as when there is evidence of impairment. During the year ended December 31, 2018, we had no long-lived assets that were subject to non-recurring fair value measurements.

The following table presents categories of long-lived assets that were subject to non-recurring fair value measurements during the year ended December 31, 2017 (in thousands):


			Fair Value Measurements at the End of the Reporting Period Using
			Quoted Prices
			in Active		Significant
	Carrying		Markets for		Other		Significant		Total
	Value at		Identical Assets		Observable		Unobservable		Non-Cash
	December 31,		and Liabilities		Inputs		Inputs		Impairment
	2017		(Level 1)		(Level 2)		(Level 3)		Loss

Oil and gas properties —
Investment in AREC	$	425	$	—	$	425	$	—	$	3,505
Investment in VestaCare	—		—		—		—		2,500
									$	6,005

The following table presents categories of long-lived assets that were subject to non-recurring fair value measurements during the year ended December 31, 2016 (in thousands):


			Fair Value Measurements at the End of the Reporting Period Using
			Quoted Prices
			in Active		Significant
	Carrying		Markets for		Other		Significant		Total
	Value at		Identical Assets		Observable		Unobservable		Non-Cash
	December 31,		and Liabilities		Inputs		Inputs		Impairment
	2016		(Level 1)		(Level 2)		(Level 3)		Loss

Investment in Bencap	$	—	$	—	$	—	$	—	$	2,200
Oil and gas properties	62,784		—		—		62,784		313
									$	2,513