ACQUISITION OF REVERE BANK (Details) $ / shares in Units, $ in Thousands		3 Months Ended
Apr. 01, 2020 USD ($) $ / shares shares	Mar. 31, 2020 USD ($) Banks
Pending acquisition [Line Items]
Closing price \| $ / shares	$ 22.64
Transaction value	$ 293,002
Assets acquired	2,846,030
Provisional amount of goodwill recognized as of the Acquisition Date	$ 839
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		$ 293,000
Scenario, Plan [Member] \| Maryland-based Revere [Member]
Pending acquisition [Line Items]
Assets acquired		$ 2,800,000
Number of Banking Offices \| Banks		11

The rate of shares exchanged in business combination.

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- Definition

The provisional amount of goodwill recongnized and it to be finanlized within twelve months, arising from business combination.

+ References

No definition available.

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Number of Banking Offices.

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- Definition

The percentage of voting share held in a newly acquired business

+ References

No definition available.

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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.

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

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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

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-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
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Amount of assets acquired at the acquisition date.

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