Credit Losses

12 Months Ended

Dec. 31, 2020

The Company is exposed to credit losses primarily through the provision of its executive search and consulting services. The Company’s expected credit loss allowance methodology for accounts receivable is developed using historical collection experience, current and future economic and market conditions and a review of the current status of customers' trade accounts receivables. Due to the short-term nature of such receivables, the estimate of amount of accounts receivable that may not be collected is primarily based on historical loss-rate experience. When required, the Company adjusts the loss-rate methodology to account for current conditions and reasonable and supportable expectations of future economic and market conditions. The Company generally assesses future economic conditions for a period of sixty to ninety days, which corresponds with the contractual life of its accounts receivables. Additionally, specific allowance amounts are established to record the appropriate provision for customers that have a higher probability of default. The Company’s monitoring activities include timely account reconciliation, dispute resolution, payment confirmation, consideration of customers' financial condition and macroeconomic conditions. Balances are written off when determined to be uncollectible. The Company considered the current and expected future economic and market conditions surrounding the COVID-19 pandemic and determined that the estimate of credit losses was not significantly impacted.

The activity in the allowance for credit losses on the Company's trade receivables is as follows:


	December 31,
	2020		2019		2018
Balance at January 1,	$	5,140	$	3,502	$	2,534
Provision for credit losses	6,696		5,900		3,790
Write-offs	(5,418)		(4,270)		(2,708)
Foreign currency translation	139		8		(114)
Balance at December 31,	$	6,557	$	5,140	$	3,502

The fair value and unrealized losses on available for sale debt securities, aggregated by investment category and the length of time the security has been in an unrealized loss position, are as follows:


	Less Than 12 Months				Balance Sheet Classification
Balance at December 31, 2020	Fair Value		Unrealized Loss		Cash and Cash Equivalents		Marketable Securities
U.S. Treasury securities	$	31,997	$	1	$	31,997	$	—

The unrealized loss on one investment in U.S. Treasury securities at December 31, 2020 was caused by fluctuations in market interest rates. The contractual cash flows of these investments are guaranteed by an agency of the U.S. government. Accordingly, it is expected that the investments would not be settled at a price less than the amortized cost basis. The Company does not intend to sell the investments and it is not more likely than not that the Company will be required to sell the investments before the recovery of the amortized cost basis. There were no investments with unrealized losses at December 31, 2019.