Stockholders' Equity (Details 2) - $ / shares	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Number of Options	134,150	150,138	231,941
Weighted Average Exercise Price	$ 85.22	$ 67.99	$ 81.15
Lower limit of exercise price	28.50
Upper limit of exercise price	$ 239.40
2016 [Member]
Number of Options	197
Weighted Average Exercise Price	$ 234.06
Lower limit of exercise price	233.10
Upper limit of exercise price	$ 239.40
2017 [Member]
Number of Options
Weighted Average Exercise Price
Lower limit of exercise price
Upper limit of exercise price
2018 [Member]
Number of Options	1,954
Weighted Average Exercise Price	$ 32.01
Lower limit of exercise price	31.20
Upper limit of exercise price	$ 44.40
2019 [Member]
Number of Options	534
Weighted Average Exercise Price	$ 32.81
Lower limit of exercise price	28.50
Upper limit of exercise price	$ 40.00
2020 and later [Member]
Number of Options	131,465
Weighted Average Exercise Price	$ 86.00
Lower limit of exercise price	70.00
Upper limit of exercise price	$ 100.00