| Document and Entity Information | Nov. 12, 2021 |
| Entity Information [Line Items] | |
| Document Type | 8-K/A |
| Amendment Flag | true |
| Document Period End Date | Nov. 12, 2021 |
| Entity Incorporation, State or Country Code | MA |
| Entity File Number | 1-9047 |
| Entity Tax Identification Number | 04-2870273 |
| Entity Registrant Name | INDEPENDENT BANK CORP. |
| Entity Address, Address Line One | 2036 Washington Street |
| Entity Address, City or Town | Hanover |
| Entity Address, State or Province | MA |
| Entity Address, Postal Zip Code | 02339 |
| City Area Code | 781 |
| Local Phone Number | 878-6100 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Title of 12(b) Security | Common Stock, $0.01 par value per share |
| Trading Symbol | INDB |
| Security Exchange Name | NASDAQ |
| Entity Emerging Growth Company | false |
| Amendment Description | On November 15, 2021, Independent Bank Corp. (“Independent”) filed a Current Report on Form 8-K (the “Original Report”) to disclose the completion on November 12, 2021 of its previously announced acquisition of Meridian Bancorp, Inc. (“Meridian”) pursuant to an Agreement and Plan of Merger, dated as of April 22, 2021, by and among Independent, Rockland Trust Company (“Rockland Trust”), Bradford Merger Sub Inc. (“Merger Sub”), Meridian and East Boston Savings Bank (“East Boston”). Pursuant to the Merger Agreement, upon the terms and subject to the conditions set forth in the Merger Agreement, among other things, (i) Merger Sub merged with and into Meridian, with Meridian continuing as the surviving entity (the “Merger” and the effective time of the Merger, the “Effective Time”), (ii) immediately after the Merger, Meridian merged with and into Independent, with Independent continuing as the surviving entity (the “HoldCo Merger”) and (iii) immediately following the HoldCo Merger, East Boston merged with and into Rockland Trust, with Rockland Trust continuing as the surviving entity (the “Bank Merger” and, together with the Merger and the HoldCo Merger, the “Transaction”).This Form 8-K/A amends the Original Report to include the historical audited financial statements of Meridian and the unaudited pro forma combined financial information required by Items 9.01(a) and 9.01(b) of Form 8-K, which were excluded from the Initial 8-K in reliance on the instructions to such items. |
| Entity Central Index Key | 0000776901 |
| Mailing Address [Member] | |
| Entity Information [Line Items] | |
| Entity Address, Address Line One | 288 Union Street |
| Entity Address, City or Town | Rockland |
| Entity Address, State or Province | MA |
| Entity Address, Postal Zip Code | 02370 |
