4. Goodwill

We review the carrying value of our goodwill in the fourth quarter of every year, or whenever events indicate impairment may have occurred, to determine if the estimated recoverable value of our reporting unit exceeds its net carrying value (including the applicable goodwill).

A qualitative assessment is performed to determine whether it is more likely than not that the fair value of the reporting unit is impaired. If it is more likely than not, we perform a goodwill impairment test. We determine the fair value of our reporting unit using both the expected present value of future cash flows and a market approach. Each approach is weighted 50% in determining our calculated fair value. The present value of future cash flows is estimated using our most recent forecast and the weighted average cost of capital. The market approach uses a market multiple on the reporting unit’s earnings before interest expense, provision for income taxes and depreciation and amortization expense. Significant estimates for our reporting unit included in our impairment analysis are our cash flow forecasts, our estimate of the market’s weighted average cost of capital and market multiples. Changes in forecasts, cost of capital and market multiples could affect the estimated fair value of our reporting unit and result in a goodwill impairment charge in a future period.

Management must apply judgment in determining the estimated fair value of our reporting unit for purposes of performing a goodwill impairment test. Management uses all available information to make this fair value determination, including the present values of expected future cash flows using discount rates commensurate with the risks involved in the assets.

For the years ended December 31, 2014, 2013 and 2012, we determined that there was no impairment of goodwill.

For the years ended December 31, 2013 and 2012, there were no additions or acquisitions that resulted in the recognition of goodwill. The following table presents the change in the net carrying amount of goodwill for the year ended December 31, 2014 (in thousands):

	December 31, 2014
Goodwill as of January 1, 2014(1)	$	124,019
Goodwill acquired during year	3,738
Goodwill as of December 31, 2014(1)	$	127,757

(1)We do not have any accumulated impairment losses.