Income Taxes (Details) - USD ($)	12 Months Ended
	Jan. 31, 2019	Jan. 31, 2018	Jan. 31, 2017	Jan. 31, 2016
Income Tax Disclosure [Abstract]
Deferred Tax Assets, Tax Credit Carryforwards	$ 26,523,000	$ 3,897,000
Deferred Tax Assets, Valuation Allowance	$ 232,000	$ 241,000	$ 417,000	$ 1,151,000
Valuation Allowance, Methodologies and Assumptions	$9,000	$176,000	$734,000
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	21.00%	33.80%	35.00%
Deferred Other Tax Expense (Benefit)	$ (14,362,000)
Tax Adjustments, Settlements, and Unusual Provisions	272,000
Tax Credit Carryforward, Amount	21,200,000	$ 11,500,000
Deferred Federal, State and Local, Tax Expense (Benefit)	4,600,000
Income Taxes Paid	855,000	6,920,000	$ 7,090,000
Proceeds from Income Tax Refunds	1,132,000	476,000	150,000
Unrecognized Tax Benefits	8,785,000	$ 2,325,000	$ 2,096,000
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued	447,000
Increase (Decrease) in Provision For Income Taxes	$ (8,304,000)