Stock Repurchase Program and Cash Dividend (Details Textual 1) - $ / shares	1 Months Ended	3 Months Ended
	Mar. 09, 2018	Jan. 31, 2018	Jan. 31, 2017
Subsequent Event [Line Items]
Treasury Stock, Shares, Acquired		4,427,000	557,000
Treasury Stock Acquired, Average Cost Per Share		$ 47.43	$ 27.33
Subsequent Event [Member]
Subsequent Event [Line Items]
Treasury Stock, Shares, Acquired	1,800,000
Treasury Stock Acquired, Average Cost Per Share	$ 45.44