Allowance for Doubtful Accounts Receivable and Sales Returns

Activity in the allowance for doubtful accounts receivable and sales returns (in thousands):



	Allowance For
	Doubtful Accounts Receivable			Sales Returns
Balances, December 31, 2013	$	966		$	569
Addition (reduction) to allowance	403			(185		)
Amounts written off	—			(5		)
Foreign currency translation	(54		)	(1		)
Balances, September 30, 2014	$	1,315		$	378

One customer accounted for 17% of trade accounts receivable and one other customer accounted for 14% of trade accounts receivable, as of September 30, 2014. One customer accounted for 17% of trade accounts receivable as of December 31, 2013.

One customer accounted for 24% and 20% of consolidated revenue, or $8.2 million and $24.6 million, during the quarter and nine months ended September 30, 2014, and is reflected in our Mobile Entertainment segment. One customer accounted for approximately 12% and 14% of consolidated revenue, or $6.0 million and $21.1 million, during the quarter and nine months ended September 30, 2013, and is reflected in our RealPlayer Group and Games segments. One additional customer accounted for approximately 14%, or $6.8 million, and 11% or $17.3 million, of consolidated revenue during the quarter and nine months ended September 30, 2013, respectively, and is reflected in our Mobile Entertainment segment.