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Summary of Significant Accounting Policies (Amortized Cost, Fair Value, and Corresponding Amount of Gross Unrealized Gains and Losses Recognized in AOCI of Available-for-Sale Security) (Details) - USD ($) $ in Thousands | Feb. 02, 2020 | Feb. 03, 2019
--- | --- | ---
Debt Securities, Available-for-sale [Line Items] |  |
Estimated Fair Value | $ 6,432 | $ 6,295
Level 3 Security [Member] | Corporate Trust [Member] |  |
Debt Securities, Available-for-sale [Line Items] |  |
Cost or Amortized Cost | 6,178 |
Gross Unrealized Gains | 254 |
Estimated Fair Value | $ 6,432 |

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- Definition Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27161-111563 + Details
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- Definition This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any. + References No definition available. + Details
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