Note 5 - Loans and Allowance for Credit Losses - Loans (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Dec. 31, 2015	Sep. 30, 2015
Commercial Portfolio Segment [Member]
Loans	$ 1,130,042	$ 1,052,257	$ 1,007,659
Loans, percent	21.00%	21.00%	21.00%
Income Producing Portfolio Segment [Member]
Loans	$ 2,551,186	$ 2,115,478	$ 2,022,950
Loans, percent	46.00%	42.00%	42.00%
Owner Occupied Portfolio Segment [Member]
Loans	$ 590,427	$ 498,103	$ 489,657
Loans, percent	11.00%	10.00%	10.00%
Residential Portfolio Segment [Member]
Loans	$ 154,439	$ 147,365	$ 147,720
Loans, percent	3.00%	3.00%	3.00%
Construction Portfolio Segment [Member] \| Commercial and Residential Loan [Member]
Loans	$ 838,137	$ 985,607	$ 927,265
Loans, percent	15.00%	20.00%	20.00%
Construction Portfolio Segment [Member] \| Commercial and Industrial Loan [Member]
Loans	$ 104,676	$ 79,769	$ 60,487
Loans, percent	2.00%	2.00%	1.00%
Construction Portfolio Segment [Member]
Loans	$ 942,813	$ 1,065,376	$ 987,752
Home Equity Portfolio Segment [Member]
Loans	$ 106,856	$ 112,885	$ 115,346
Loans, percent	2.00%	2.00%	3.00%
Other Consumer Portfolio Segment [Member]
Loans	$ 6,212	$ 6,904	$ 5,881
Loans, percent
Loans	$ 5,481,975	$ 4,998,368	$ 4,776,965
Loans, percent	100.00%	100.00%	100.00%
Less: Allowance for Credit Losses	$ (56,864)	$ (52,687)	$ (50,320)
Net loans	$ 5,425,111	$ 4,945,681	$ 4,726,645

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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- 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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- Details

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- Details

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