Stockholders Equity Dividend (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended							9 Months Ended		0 Months Ended
	Oct. 31, 2014	Jul. 31, 2014	Apr. 30, 2014	Jan. 31, 2014	Oct. 31, 2013	Jul. 31, 2013	Apr. 30, 2013	Oct. 31, 2014	Oct. 31, 2013	Nov. 20, 2014 Subsequent Event [Member]
Stockholders' Equity Attributable to Parent [Abstract]
Common Stock Dividend Per Share Annual Amount							$ 0.18
Dividends Payable [Line Items]
Dividends Payable, Date Declared	Aug. 21, 2014	May 22, 2014	Feb. 27, 2014	Nov. 21, 2013	Aug. 22, 2013	May 23, 2013	Mar. 07, 2013			Nov. 20, 2014
Dividends Payable, Date of Record	Sep. 10, 2014	Jun. 10, 2014	Mar. 10, 2014	Dec. 10, 2013	Sep. 10, 2013	Jun. 10, 2013	Mar. 22, 2013			Dec. 10, 2014
Dividends Payable, Date to be Paid	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Jan. 02, 2014	Sep. 30, 2013	Jul. 01, 2013	Apr. 10, 2013			Jan. 02, 2015
Cash dividends declared per common share	$ 0.050	$ 0.050	$ 0.050	$ 0.045	$ 0.045	$ 0.045	$ 0.045	$ 0.150	$ 0.135	$ 0.050
Payments of Dividends	$ 5,697	$ 5,693	$ 5,778	$ 5,159	$ 5,096	$ 5,079	$ 5,064	$ 17,168	$ 15,239