Employee Benefit Plans (Tables)

9 Months Ended

Sep. 30, 2012

Compensation and Retirement Disclosure [Abstract]

Schedule of Components of Net Periodic Benefit Costs

The components of net periodic benefit cost are as follows:

	Three months ended						Nine months ended
	September 30,						September 30,
	2012			2011			2012			2011
Service cost	$	1,061		$	1,133		$	3,422		$	3,197
Interest cost	110			106			338			294
Expected return on plan assets	(125		)	(108		)	(385		)	(307		)
Employee contributions	(283		)	(274		)	(868		)	(781		)
Amortization	73			64			224			182
Total net periodic benefit cost	$	836		$	921		$	2,731		$	2,585