Defined Benefit Plans

3 Months Ended

Mar. 31, 2016

Compensation and Retirement Disclosure [Abstract]

Employee Benefit Plans

Defined Benefit Plans

We maintain defined benefit plans for employees in certain countries outside the United States, including retirement benefit plans required by applicable local law. The plans are valued by independent actuaries using the projected unit credit method. The liabilities correspond to the projected benefit obligations of which the discounted net present value is calculated based on years of employment, expected salary increases, and pension adjustments.

The components of net periodic benefit cost are as follows:

	Three months ended
	March 31,
	2016			2015
Service cost	$	2,023		$	2,421
Interest cost	60			180
Expected return on plan assets	(163		)	(243		)
Employee contributions	(352		)	(427		)
Amortization	114			311
Total net periodic benefit cost	$	1,682		$	2,242