Investments (Details) - Schedule of Equity Method Investments (USD $) In Thousands, unless otherwise specified	Apr. 30, 2014	Jan. 31, 2014
Schedule of Equity Method Investments [Line Items]
Total Equity Method Investments, Carrying Amount	$ 74,439	$ 71,189
Big River [Member]
Schedule of Equity Method Investments [Line Items]
Total Equity Method Investments, Ownership Percentage	10.00%
Total Equity Method Investments, Carrying Amount	40,090	40,042
Patriot [Member]
Schedule of Equity Method Investments [Line Items]
Total Equity Method Investments, Ownership Percentage	27.00%
Total Equity Method Investments, Carrying Amount	$ 34,349	$ 31,147