Accounts Receivable

12 Months Ended

Dec. 31, 2014

Accounts Receivable [Abstract]

Accounts Receivable

4. ACCOUNTS RECEIVABLE

Accounts receivable consists of the following:

	December 31,
	2013			2014
Accounts receivable	$	54,743			156,697
Allowance for doubtful accounts		(145	)		(2,410	)
Accounts receivable, net	$	54,598		$	154,287

Movement of allowance for doubtful accounts is as follows:

	December 31,
	2012			2013			2014
Balance at beginning of year	$	68		$	213		$	145
Addition in connection with business acquisition		-			-			2,020
Charge to expense		154			157			349
Write offs during the year		(10	)		(229	)		(74	)
Exchange rate differences		1			4			(30	)
Balance at end of year	$	213		$	145		$	2,410