Deposits - Interest expense on deposits (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Deposits Liabilities, Balance Sheet, Reported Amounts [Abstract]
Interest bearing transaction	$ 3,190	$ 6,491	$ 3,348
Savings and money market	26,272	50,042	35,534
Time, $100,000 or more	13,464	20,016	17,138
Other time	10,640	14,477	4,190
Total	53,566	91,026	$ 60,210
Time Deposits 100,000 Or More gross	$ 100	$ 100

Interest expense interest bearing transaction deposits.

No definition available.

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Period Type:	duration

- Definition

Amount of time deposit liabilities, including certificates of deposit, in denominations of $100,000 or more.

+ References

No definition available.

+ Details

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Namespace Prefix:	egbn_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- References

No definition available.

+ Details

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- Definition

Aggregate amount of interest expense on all deposits.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.6)
-URI http://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260

+ Details

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- Definition

The aggregate interest expense incurred on the following for deposits in domestic offices: (1) transaction accounts (NOW, and telephone and preauthorized transfer accounts), (2) money market deposits and (3) savings deposits.

+ References

+ Details

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- Definition

Interest expense incurred on time deposits, including certificates of deposits, of $100,000 or more in domestic offices.

+ References

+ Details

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- Definition

Interest expense incurred on time deposits, including certificates of deposits, less than $100,000 in domestic offices.

+ References

+ Details

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