POWER OF ATTORNEY

     The undersigned hereby constitutes and appoints each of Kathleen C. Henry,
Astrid E. P. Tsang, Michael K. Krebs, Kathleen R. Henry and Malissa Daniels,
signing singly, as the undersigned's true and lawful attorney-in-fact to:

     (1)   execute, for and on behalf of the undersigned, in the undersigned's
           capacity as a beneficial owner, joint actor, or similar capacity of
           securities which are registered under or subject to the laws, rules
           or regulations of any jurisdiction, any form, schedule, report or
           other similar document as may be required by such jurisdiction's
           laws, rules or regulations, and any amendments thereto, in accordance
           with such jurisdiction's laws, rules or regulations, including
           without limitation (a) Forms 3, 4 and 5 in accordance with Section
           16(a) of the Securities Exchange Act of 1934 (the "Exchange Act") and
           the rules thereunder, (b) Schedule 13D or 13G in accordance with
           Section 13(d) of the Exchange Act and the rules thereunder, (c) Form
           144 under the Securities Act of 1933, and (d) a Uniform Application
           for Access Codes to File on EDGAR on Form ID;

     (2)   do and perform any and all acts for and on behalf of the undersigned
           which may be necessary or desirable to complete and execute any such
           form, schedule, report or other similar document, and timely file
           such form, schedule, report or other similar document, including one
           or more amendments thereto, with the United States Securities and
           Exchange Commission (the "SEC") or any other appropriate governmental
           authority or regulatory body of the relevant jurisdiction and any
           stock exchange or similar authority; and

     (3)   take any other action of any type whatsoever in connection with the
           foregoing which, in the opinion of such attorney-in-fact, may be of
           benefit to, in the best interest of, or legally required by, the
           undersigned, it being understood that the documents executed by such
           attorney-in-fact on behalf of the undersigned pursuant to this Power
           of Attorney shall be in such form and shall contain such terms and
           conditions as such attorney-in-fact may approve in such attorney-in-
           fact's discretion.

     The undersigned hereby grants to each such attorney-in-fact full power and
authority to do and perform any and every act and thing whatsoever requisite,
necessary, or proper to be done in the exercise of any of the rights and powers
herein granted, as fully to all intents and purposes as the undersigned might or
could do if personally present, with full power of substitution or revocation.
The undersigned acknowledges that the foregoing attorneys-in-fact, in serving
in such capacity at the request of the undersigned, are not assuming any of the
undersigned's responsibilities to comply with the securities laws, rules or
regulations of any particular jurisdiction.

     This Power of Attorney shall remain in full force and effect until the
undersigned is no longer required to file forms, schedules, or similar documents
with respect to the undersigned's holdings of and transactions in securities
which are registered under the laws, rules or regulations of any jurisdiction,
unless earlier revoked by the undersigned in a signed writing delivered to the
foregoing attorneys-in-fact.

     IN WITNESS WHEREOF, the undersigned has caused this Power of Attorney to be
executed as of the date below.

                            Signature:    /s/ Gregory P. Buscone

                            Print Name:   Gregory P. Buscone

                            Date:         February 18, 2022