Activity in allowance accounts related to accounts receivable and deferred tax assets consisted of the following:


	Balance at Beginning of Year		Charged to Operations			Deductions			Balance at End of Year
Year ended December 31, 2011:
Accounts receivable allowances	$	856		990	⁽¹⁾		(609	)⁽²⁾	$	1,237
Deferred tax asset valuation allowance	$	607		368			—		$	975
Year ended December 31, 2012:
Accounts receivable allowances	$	1,237		1,509	⁽¹⁾		(1,859	)⁽²⁾	$	887
Deferred tax asset valuation allowance	$	975		1,606			—		$	2,581
Year ended December 31, 2013:
Accounts receivable allowances	$	887		1,601	⁽¹⁾		(1,093	)⁽²⁾	$	1,395
Deferred tax asset valuation allowance	$	2,581		442			—		$	3,023

(1)	Amounts represent charges to general and administrative expense for increases to the allowance for doubtful accounts.

(2)	Amounts represent cash collections from customers for accounts previously reserved and write-offs of accounts receivable recorded against the allowance for doubtful accounts.