Investments (Held-To-Maturity Securities) (Details) - USD ($) $ in Thousands	Nov. 03, 2018	Feb. 03, 2018
Contractual maturities of held-to-maturity securities, at amortized cost:
Less than 1 year, Amortized Cost	$ 45,605
1 - 5 years, Amortized Cost	4,518
Held-to-Maturity Securities, Amortized Cost	50,123
Contractual maturities of held-to-maturity securities, at fair values:
Less than 1 year, Fair Value	45,538
1 - 5 years, Fair Value	4,518
Held-to-Maturity Securities, Estimated Fair Value	$ 50,056	$ 55,460

Amount of investment in debt security measured at amortized cost (held-to-maturity).

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