Accrued Expenses

Accrued expenses consist of (table in thousands):



	September 30, 2012		December 31, 2011
Salaries and benefits	$	938,841	$	961,587
Product warranties	264,817		254,554
Partner rebates	153,552		167,813
Restructuring, current (See Note 13)	69,578		61,541
Derivatives	29,589		50,963
Other	861,191		858,521
	$	2,317,568	$	2,354,979

Product Warranties

Systems sales include a standard product warranty. At the time of the sale, we accrue for systems’ warranty costs. The initial systems’ warranty accrual is based upon our historical experience, expected future costs and specific identification of systems’ requirements. Upon sale or expiration of the initial warranty, we may sell additional maintenance contracts to our customers. Revenue from these additional maintenance contracts is included in deferred revenue and recognized ratably over the service period. The following represents the activity in our warranty accrual for the three and nine months ended September 30, 2012 and 2011 (table in thousands):



	For the Three Months Ended						For the Nine Months Ended
	September 30, 2012			September 30, 2011			September 30, 2012			September 30, 2011
Balance, beginning of the period	$	262,059		$	248,395		$	254,554		$	236,131
Provision	41,303			42,535			129,358			130,775
Amounts charged to the accrual	(38,545		)	(41,955		)	(119,095		)	(117,931		)
Balance, end of the period	$	264,817		$	248,975		$	264,817		$	248,975

The provision includes amounts accrued for systems at the time of shipment, adjustments for changes in estimated costs for warranties on systems shipped in the period and changes in estimated costs for warranties on systems shipped in prior periods. It is not practicable to determine the amounts applicable to each of the components.