Note 5 - Loans and Allowance for Credit Losses - Loans (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015	Mar. 31, 2015
Commercial Portfolio Segment [Member]
Loans, amount	$ 1,060,047	$ 1,052,257	$ 933,715
Loan Percent	21.00%	21.00%	21.00%
Less: Allowance for Credit Losses			$ (13,777)
Income Producing Portfolio Segment [Member]
Loans, amount	$ 2,138,091	$ 2,115,478	$ 1,739,483
Loan Percent	40.00%	42.00%	40.00%
Less: Allowance for Credit Losses			$ (11,652)
Owner Occupied Portfolio Segment [Member]
Loans, amount	$ 569,915	$ 498,103	$ 493,003
Loan Percent	11.00%	10.00%	11.00%
Less: Allowance for Credit Losses			$ (3,127)
Residential Portfolio Segment [Member]
Loans, amount	$ 149,159	$ 147,365	$ 147,871
Loan Percent	3.00%	3.00%	3.00%
Less: Allowance for Credit Losses			$ (1,055)
Construction Portfolio Segment [Member] \| Commercial and Residential Loan [Member]
Loans, amount	$ 1,034,689	$ 985,607	$ 862,013
Loan Percent	20.00%	20.00%	19.00%
Construction Portfolio Segment [Member] \| Commercial and Industrial Loan [Member]
Loans, amount	$ 87,324	$ 79,769	$ 49,558
Loan Percent	2.00%	2.00%	1.00%
Construction Portfolio Segment [Member]
Loans, amount	$ 1,122,013	$ 1,065,376	$ 911,571
Less: Allowance for Credit Losses			(16,383)
Home Equity Portfolio Segment [Member]
Loans, amount	$ 110,985	$ 112,885	$ 120,543
Loan Percent	3.00%	2.00%	3.00%
Less: Allowance for Credit Losses			$ (1,509)
Other Consumer Portfolio Segment [Member]
Loans, amount	$ 5,661	$ 6,904	$ 98,707
Loan Percent			2.00%
Less: Allowance for Credit Losses			$ (276)
Loans, amount	$ 5,155,871	$ 4,998,368	$ 4,444,893
Loan Percent	100.00%	100.00%	100.00%
Less: Allowance for Credit Losses	$ (54,608)	$ (52,687)	$ (47,779)
Net loans	$ 5,101,263	$ 4,945,681	$ 4,397,114

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

Name:	us-gaap_FinancingReceivableAllowanceForCreditLosses
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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- Details

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- Details

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- Details

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- Details

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