Guarantees

We provide warranties on certain of our products at the time of sale. The standard warranty period for our capital and reusable equipment is generally one year. Liability under service and warranty policies is based upon a review of historical warranty and service claim experience. Adjustments are made to accruals as claim data and historical experience warrant.

Changes in the carrying amount of service and product warranties for the year ended December 31, are as follows:



	2014			2013			2012

Balance as of January 1,	$	2,422		$	3,636		$	3,618

Provision for warranties	3,492			3,061			4,163
Claims made	(3,628		)	(4,275		)	(4,145		)

Balance as of December 31,	$	2,286		$	2,422		$	3,636