Guarantees

We provide warranties on certain of our products at the time of sale and sell extended warranties. The standard warranty period for our capital and reusable equipment is generally one year and our extended warranties can vary in length. 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:



	2016			2015			2014

Balance as of January 1,	$	2,509		$	2,286		$	2,422

Provision for warranties	2,967			3,836			3,492
Claims made	(3,522		)	(3,613		)	(3,628		)

Balance as of December 31,	$	1,954		$	2,509		$	2,286