Goodwill

12 Months Ended

Dec. 31, 2018

Goodwill And Intangible Assets Disclosure [Abstract]

Goodwill

(10) Goodwill

Changes in the carrying amount of goodwill for the years ended December 31, 2017 and 2018 are as follows (in thousands):

Balance as of December 31, 2016 and 2017	$	—
Callcap acquisition		19,031
Telmetrics acquisition		5,411
Balance as of December 31, 2018	$	24,442

We perform our annual impairment testing on November 30 and whenever events or changes in circumstances indicate the carrying value of goodwill may not be recoverable. No impairment of goodwill has been identified in 2018. The testing of goodwill for impairment requires the Company to make significant estimates about its future performance and cash flows, as well as other assumptions. Events and circumstances considered in determining whether the carrying value of goodwill may not be recoverable include, but are not limited to: significant changes in performance relative to expected operating results; significant changes in the use of the assets; significant changes in competition and market dynamics; significant and sustained declines in the Company’s stock price and market capitalization; a significant decline in its expected future cash flows or a significant adverse change in the Company’s business climate. These estimates and circumstances are inherently uncertain and can be affected by numerous factors, including changes in economic, industry or market conditions, changes in business operations, a loss of a significant customer, changes in competition, volatility in financial markets, or changes in the share price of the Company’s common stock and market capitalization.