Note 5 - Loans and Allowance for Credit Losses - Loans (Details) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015	Jun. 30, 2015
Commercial Portfolio Segment [Member]
Loans, amount	$ 1,140,863	$ 1,052,257	$ 960,506
Loan Percent	21.00%	21.00%	21.00%
Less: Allowance for Credit Losses	$ (13,386)
Income Producing Portfolio Segment [Member]
Loans, amount	$ 2,461,581	$ 2,115,478	$ 1,863,583
Loan Percent	45.00%	42.00%	41.00%
Less: Allowance for Credit Losses	$ (19,072)
Owner Occupied Portfolio Segment [Member]
Loans, amount	$ 584,358	$ 498,103	$ 497,834
Loan Percent	11.00%	10.00%	11.00%
Less: Allowance for Credit Losses	$ (4,202)
Residential Portfolio Segment [Member]
Loans, amount	$ 150,129	$ 147,365	$ 149,842
Loan Percent	3.00%	3.00%	3.00%
Less: Allowance for Credit Losses	$ (1,061)
Construction Portfolio Segment [Member] \| Commercial and Residential Loan [Member]
Loans, amount	$ 847,268	$ 985,607	$ 901,617
Loan Percent	16.00%	20.00%	20.00%
Construction Portfolio Segment [Member] \| Commercial and Industrial Loan [Member]
Loans, amount	$ 100,063	$ 79,769	$ 54,134
Loan Percent	2.00%	2.00%	1.00%
Construction Portfolio Segment [Member]
Loans, amount	$ 947,331	$ 1,065,376	$ 955,751
Less: Allowance for Credit Losses	(17,024)
Home Equity Portfolio Segment [Member]
Loans, amount	$ 110,697	$ 112,885	$ 118,544
Loan Percent	2.00%	2.00%	3.00%
Less: Allowance for Credit Losses	$ (1,556)
Other Consumer Portfolio Segment [Member]
Loans, amount	$ 8,470	$ 6,904	$ 4,837
Loan Percent
Less: Allowance for Credit Losses	$ (235)
Loans, amount	$ 5,403,429	$ 4,998,368	$ 4,550,897
Loan Percent	100.00%	100.00%	100.00%
Less: Allowance for Credit Losses	$ (56,536)	$ (52,687)	$ (48,921)
Net loans	$ 5,346,893	$ 4,945,681	$ 4,501,976

Percent of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

No definition available.

+ Details

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Namespace Prefix:	egbn_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

A valuation allowance for financing receivables that are expected to be uncollectible.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953423-111524

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=65884687&loc=d3e4428-111522

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5074-111524

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=65884687&loc=d3e4428-111522

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.7)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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- Details

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