Fair Value Measurements (Available-For-Sale Marketable Securities with Unrealized Losses) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Fair Value Measurements
In a Loss Position for Less Than 12 Months, Gross Unrealized Losses	$ (2)
In a Loss Position for Less Than 12 Months, Estimated Fair Value	$ 9,443
Maximum contractual maturities of Company's available-for-sale marketable securities	1 year	1 year
Corporate debt securities
Fair Value Measurements
In a Loss Position for Less Than 12 Months, Gross Unrealized Losses	$ (2)
In a Loss Position for Less Than 12 Months, Estimated Fair Value	$ 9,443