PENDING ACQUISITION (Details) $ in Billions	12 Months Ended
Dec. 31, 2019 USD ($) Banks	Sep. 23, 2019
Revere Bank Shareholders [Member]
Business Acquisition [Line Items]
Ratio of shares business combinations consideration transferred		1.05
Revere Bank [Member]
Business Acquisition [Line Items]
Effective Date of Acquisition	Sep. 23, 2019
Assets acquired \| $	$ 2.8
Number of Banking Offices \| Banks	11
The combined company [Member] \| Sandy Spring Shareholders [Member]
Business Acquisition [Line Items]
Percentage of voting interests acquired, combined co.		74.00%
The combined company [Member] \| Revere Bank Shareholders [Member]
Business Acquisition [Line Items]
Percentage of voting interests acquired, combined co.		26.00%

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The ratio of shares in business combination for consideration transferred.

+ References

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Date when the acquirer obtains control of the acquiree, in CCYY-MM-DD format.

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Percentage of voting equity interests acquired at the acquisition date in the business combination.

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Amount of assets acquired at the acquisition date.

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