Stockholders' Equity (Details 1) - USD ($) $ in Thousands	3 Months Ended
Apr. 30, 2020	Apr. 30, 2019
Total stock-based compensation	$ 163,886	$ 201,708
Total income tax benefit recognized for stock-based compensation arrangements	34,416	42,359
Restricted Stock
Total stock-based compensation	149,539	201,829
Stock Options
Total stock-based compensation	14,347	0
2017 Plan
Total stock-based compensation	163,886	201,829
Stock Appreciation Rights
Total stock-based compensation	$ 0	$ (121)

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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