ACQUISITION OF REVERE BANK (Details) $ / shares in Units, $ in Millions	3 Months Ended
Mar. 31, 2020 USD ($) Banks $ / shares	Apr. 01, 2020 shares
Sandy Spring Shareholders [Member]
Pending acquisition [Line Items]
Percentage of ownership in combined company		74.00%
Revere shareholders [Member]
Pending acquisition [Line Items]
Percentage of ownership in combined company		26.00%
Maryland-based Revere [Member]
Pending acquisition [Line Items]
Business acquisition rate of share exchange \| shares		1.05
Closing price \| $ / shares	$ 22.64
Transaction value	$ 287
Scenario, Plan [Member] \| Maryland-based Revere [Member]
Pending acquisition [Line Items]
Assets acquired	$ 2,800
Number of Banking Offices \| Banks	11

The rate of shares exchanged in business combination.

No definition available.

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- Definition

Number of Banking Offices.

+ References

No definition available.

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- Definition

The percentage of voting share held in a newly acquired business

+ References

No definition available.

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Price of a single share of a number of saleable stocks paid or offered to be paid in a business combination.

+ References

No definition available.

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- Definition

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
-Paragraph 8
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- Definition

Amount of assets acquired at the acquisition date.

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