Name:	bke_OtherThanTemporaryImpairmentLossesInvestmentsHeldtoMaturitySecuritiesAtPointInTime
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This item represents other-than-temporary impairment for securities, at a point in time, which are categorized as trading securities.

No definition available.

Name:	bke_OtherThanTemporaryImpairmentLossesTradingSecuritiesSecuritiesAtPointInTime
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This item represents the gross unrealized gains for securities, at a point in time, which are categorized as trading securities.

No definition available.

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Data Type:	xbrli:monetaryItemType
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This item represents the gross unrealized losses for securities, at a point in time, which are categorized as trading securities.

No definition available.

Name:	bke_TradingSecuritiesUnrecognizedLoss
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- References

No definition available.

Name:	us-gaap_DebtSecuritiesTradingAndEquitySecuritiesFvNiAbstract
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Cost of investment in debt investment in debt security measured at fair value with change in fair value recognized in net income (trading) and investment in equity security with change in fair value recognized in net income (FV-NI). Excludes equity method investment and investment in equity security without readily determinable fair value.

No definition available.

Name:	us-gaap_DebtSecuritiesTradingAndEquitySecuritiesFvNiCost
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Amount of accumulated unrecognized gain on investment in debt security measured at amortized cost (held-to-maturity).

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

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Amount, before other-than-temporary impairment (OTTI) accretion, of investment in debt securities measured at amortized cost (held-to-maturity).

No definition available.

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- References

No definition available.

Name:	us-gaap_HeldToMaturitySecuritiesClassifiedAbstract
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Fair value of investment in debt security measured at amortized cost (held-to-maturity).

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Amount of investment in debt security measured at fair value with change in fair value recognized in net income (trading) and investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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