Note 4 - Investment Securities Available-for-Sale (Details) (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Note 4 - Investment Securities Available-for-Sale (Details) [Line Items]
Debt Securities Weighted Average Duration	4 years
Federal Home Loan Bank Stock and Federal Reserve Bank Stock	$ 22,560,000	$ 11,272,000
Available-for-sale Securities, Gross Realized Gains	298,000	237,000	941,000
Available-for-sale Securities, Gross Realized Losses	276,000	218,000	251,000
Proceeds from Sale and Maturity of Marketable Securities	49,910,000	22,100,000	77,100,000
Available-for-sale Securities Pledged as Collateral	$ 257,200,000
Percent Of Shareholders' Equity	10.00%egbn_PercentOfShareholdersEquity	10.00%egbn_PercentOfShareholdersEquity
Debt Securities [Member] \| Total Investment Securities [Member] \| Investment Securities Concentration Risk [Member]
Note 4 - Investment Securities Available-for-Sale (Details) [Line Items]
Concentration Risk, Percentage	99.90%

This item represents the weighted average duration of debt securities held.

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This item represents the percentage of the entity's stockholders' equity.

+ References

No definition available.

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- Definition

This item represents the gross profit realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

+ References

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This item represents the gross loss realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

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- Definition

The fair value of available-for-sale securities that serve as collateral for borrowings.

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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- Definition

Amount of Federal Home Loan Bank (FHLB) and Federal Reserve Bank stock.

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- Definition

The cash inflow associated with the aggregate amount received by the entity through sale or maturity of marketable securities (held-to-maturity or available-for-sale) during the period.

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-Glossary Investing Activities

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