Common Stock and Stock-Based Compensation (Tables)

3 Months Ended

Apr. 01, 2017

Summary of Stock Options under Equity Plan and Non-Employee Director Plan

Information related to stock options under the Employee Equity Incentive Plan and the Stock Option Plan for Non-Employee Directors is summarized as follows:

	Shares			Weighted- Average Exercise Price		Weighted-Average Remaining Contractual Term in Years		Aggregate Intrinsic Value (in thousands)
Outstanding at December 31, 2016		1,348,233		$	141.98
Granted		5,185			169.85
Forfeited		(4,708	)		201.91
Expired		—			—
Exercised		(166,773	)		83.16
Outstanding at April 1, 2017		1,181,937		$	173.43		6.93	$	24,673
Exercisable at April 1, 2017		199,682		$	91.22		4.04	$	12,289
Vested and expected to vest at April 1, 2017		582,117		$	113.59		5.06	$	24,054

Summary of Vesting Activities of Shares Issued Under Investment Share Program and Restricted Stock Awards

The following table summarizes vesting activities of shares issued under the investment share program and restricted stock awards:

	Number of Shares			Weighted Average Fair Value
Non-vested at December 31, 2016		64,968		$	166.29
Granted		24,671			131.64
Vested		(20,061	)		146.83
Forfeited		(380	)		101.26
Non-vested at April 1, 2017		69,198		$	159.94