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Pay vs Performance Disclosure | 12 Months Ended
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Dec. 31, 2023 USD ($) | Dec. 31, 2022 USD ($) | Dec. 31, 2021 USD ($) | Dec. 31, 2020 USD ($)
Pay vs Performance Disclosure |  |  |  |
Pay vs Performance Disclosure, Table | The following table provides the “Compensation Actually Paid,” as defined by the SEC rules (sometimes referred to below as “CAP”), to the CEO and the average compensation paid to the Company’s other named non-CEO executive officers (“Other NEOs”), along with the Company’s Total Shareholder Return (“TSR”), peer group TSR, Net Income and Return on Average Tangible Common Equity (ROATCE) for the years indicated. |  |  |
Company Selected Measure Name | ROATCE |  |  |
Named Executive Officers, Footnote | For 2023, Mr. Ruggiero, Mr. Nadeau, Ms. Harris, Mr. Rizzo and Mr. Jensen are included in the “Non-CEO NEOs” columns. For 2022, Mr. Ruggiero, Robert Cozzone, the Company’s former Chief Operating Officer, Mr. Jensen and Mr. Nadeau are included in the “Non-CEO NEOs” columns.For 2021 and 2020, Mr. Ruggiero, Mr. Cozzone, Mr. Nadeau and Edward Seksay, the Company’s former General Counsel, are included in the “Non-CEO NEOs” columns. |  |  |
Peer Group Issuers, Footnote | (4) The Peer Group TSR set forth in this table utilizes the KBW NASDAQ Bank Index, Peer Group 1, (assuming reinvestment of all dividends) and the KBW NASDAQ Regional Banking Index, Peer Group 2, (assuming reinvestment of all dividends), which we also utilize in the Total Return Performance Graph in Item 5. of the Company’s Form 10-K for the year ended December 31, 2023. The comparison assumes $100 was invested for the period starting December 31, 2019, through the end of the listed year in the company and in the KBW NASDAQ Bank Index and the KBW NASDAQ Regional Banking Index, respectively, and assumes reinvestment of all dividends. Historical stock performance is not necessarily indicative of future stock performance. |  |  |
Adjustment To PEO Compensation, Footnote | Details of the adjustments from the Summary Compensation to CAP are below, for the years indicated:
| 2023
Adjustments | Former CEO Christopher Oddleifson | Current CEO Jeffrey Tengel | Average non-CEO NEOs
Deduction for Change in the Actuarial Present Values reported under the “Change in Pension Value and Nonqualified Deferred Compensation Earnings” Column of the Summary Compensation Table for Applicable Fiscal Year ("FY") | $ | (804,577) |  | $ | — |  | $ | (52,416) |
Increase for Service Cost and, if applicable, Prior Service Cost for Pension Plans | 323,112 |  | — |  | 15,701 |
Deduction for Amounts Reported under the “Stock Awards” and “Option Awards” Columns in the Summary Compensation Table for Applicable FY | — |  | (2,008,786) |  | (249,193) |
Increase based on ASC 718 Fair Value of Awards Granted during Applicable FY that Remain Unvested as of Applicable FY End, determined as of Applicable FY End | — |  | 1,994,222 |  | 249,699 |
Increase/deduction for Awards Granted during Prior FY that were Outstanding and Unvested as of Applicable FY End, determined based on change in ASC 718 Fair Value from Prior FY End to Applicable FY End | (159,002) |  | — |  | (82,662) |
Increase based on ASC 718 Fair Value of Awards Granted during Applicable FY that Vested during Applicable FY, determined as of Vesting Date | — |  | — |  | 2,566 |
Increase/deduction for Awards Granted during Prior FY that Vested During Applicable FY, determined based on change in ASC 718 Fair Value from Prior FY End to Vesting Date | (153,164) |  | — |  | (21,842) |
Deduction of ASC 718 Fair Value of Awards Granted during Prior FY that failed to meet the applicable vesting conditions during Applicable FY, determined as of Prior FY End | (1,163,854) |  | — |  | (86,380) |
Increase based on Dividends or Other Earnings Paid during Applicable FY prior to Vesting Date | — |  | — |  | — |
Increase based on Incremental Fair Value of Options/SARs Modified during Applicable FY | — |  | — |  | — |
Total Adjustments | $ | (1,957,485) |  | $ | (14,564) |  | $ | (224,527) |
| 2022
Adjustments | Former CEO Christopher Oddleifson | Average non-CEO NEOs
Deduction for Change in the Actuarial Present Values reported under the “Change in Pension Value and Nonqualified Deferred Compensation Earnings” Column of the Summary Compensation Table for Applicable FY | $ | — |  | $ | — |
Increase for Service Cost and, if applicable, Prior Service Cost for Pension Plans | 397,084 |  | 22,880 |
Deduction for Amounts Reported under the “Stock Awards” and “Option Awards” Columns in the Summary Compensation Table for Applicable FY | (711,438) |  | (251,968) |
Increase based on ASC 718 Fair Value of Awards Granted during Applicable FY that Remain Unvested as of Applicable FY End, determined as of Applicable FY End | 993,698 |  | 350,966 |
Increase/deduction for Awards Granted during Prior FY that were Outstanding and Unvested as of Applicable FY End, determined based on change in ASC 718 Fair Value from Prior FY End to Applicable FY End | 63,357 |  | 18,830 |
Increase based on ASC 718 Fair Value of Awards Granted during Applicable FY that Vested during Applicable FY, determined as of Vesting Date | — |  | — |
Increase/deduction for Awards Granted during Prior FY that Vested During Applicable FY, determined based on change in ASC 718 Fair Value from Prior FY End to Vesting Date | 20,160 |  | 5,663 |
Deduction of ASC 718 Fair Value of Awards Granted during Prior FY that failed to meet the applicable vesting conditions during Applicable FY, determined as of Prior FY End | (240,853) |  | (60,213) |
Increase based on Dividends or Other Earnings Paid during Applicable FY prior to Vesting Date | — |  | — |
Increase based on Incremental Fair Value of Options/SARs Modified during Applicable FY | — |  | — |
Total Adjustments | $ | 522,008 |  | $ | 86,158 |
| 2021
Adjustments | Former CEO Christopher Oddleifson | Average non-CEO NEOs
Deduction for Change in the Actuarial Present Values reported under the “Change in Pension Value and Nonqualified Deferred Compensation Earnings” Column of the Summary Compensation Table for Applicable FY | $ | (155,087) |  | $ | (9,113) |
Increase for Service Cost and, if applicable, Prior Service Cost for Pension Plans | 449,226 |  | 55,598 |
Deduction for Amounts Reported under the “Stock Awards” and “Option Awards” Columns in the Summary Compensation Table for Applicable FY | (822,517) |  | (253,712) |
Increase based on ASC 718 Fair Value of Awards Granted during Applicable FY that Remain Unvested as of Applicable FY End, determined as of Applicable FY End | 926,671 |  | 285,758 |
Increase/deduction for Awards Granted during Prior FY that were Outstanding and Unvested as of Applicable FY End, determined based on change in ASC 718 Fair Value from Prior FY End to Applicable FY End | 193,722 |  | 55,349 |
Increase based on ASC 718 Fair Value of Awards Granted during Applicable FY that Vested during Applicable FY, determined as of Vesting Date | — |  | — |
Increase/deduction for Awards Granted during Prior FY that Vested During Applicable FY, determined based on change in ASC 718 Fair Value from Prior FY End to Vesting Date | 185,412 |  | 46,579 |
Deduction of ASC 718 Fair Value of Awards Granted during Prior FY that failed to meet the applicable vesting conditions during Applicable FY, determined as of Prior FY End | (67,264) |  | (16,274) |
Increase based on Dividends or Other Earnings Paid during Applicable FY prior to Vesting Date | — |  | — |
Increase based on Incremental Fair Value of Options/SARs Modified during Applicable FY | — |  | — |
Total Adjustments | $ | 710,163 |  | $ | 164,185 |
Non-PEO NEO Average Total Compensation Amount | $ 1,129,125 | $ 1,246,097 | $ 1,049,623 | $ 1,046,532
Non-PEO NEO Average Compensation Actually Paid Amount | $ 904,598 | 1,332,255 | 1,213,808 | 810,875
Adjustment to Non-PEO NEO Compensation Footnote | Details of the adjustments from the Summary Compensation to CAP are below, for the years indicated:
| 2023
Adjustments | Former CEO Christopher Oddleifson | Current CEO Jeffrey Tengel | Average non-CEO NEOs
Deduction for Change in the Actuarial Present Values reported under the “Change in Pension Value and Nonqualified Deferred Compensation Earnings” Column of the Summary Compensation Table for Applicable Fiscal Year ("FY") | $ | (804,577) |  | $ | — |  | $ | (52,416) |
Increase for Service Cost and, if applicable, Prior Service Cost for Pension Plans | 323,112 |  | — |  | 15,701 |
Deduction for Amounts Reported under the “Stock Awards” and “Option Awards” Columns in the Summary Compensation Table for Applicable FY | — |  | (2,008,786) |  | (249,193) |
Increase based on ASC 718 Fair Value of Awards Granted during Applicable FY that Remain Unvested as of Applicable FY End, determined as of Applicable FY End | — |  | 1,994,222 |  | 249,699 |
Increase/deduction for Awards Granted during Prior FY that were Outstanding and Unvested as of Applicable FY End, determined based on change in ASC 718 Fair Value from Prior FY End to Applicable FY End | (159,002) |  | — |  | (82,662) |
Increase based on ASC 718 Fair Value of Awards Granted during Applicable FY that Vested during Applicable FY, determined as of Vesting Date | — |  | — |  | 2,566 |
Increase/deduction for Awards Granted during Prior FY that Vested During Applicable FY, determined based on change in ASC 718 Fair Value from Prior FY End to Vesting Date | (153,164) |  | — |  | (21,842) |
Deduction of ASC 718 Fair Value of Awards Granted during Prior FY that failed to meet the applicable vesting conditions during Applicable FY, determined as of Prior FY End | (1,163,854) |  | — |  | (86,380) |
Increase based on Dividends or Other Earnings Paid during Applicable FY prior to Vesting Date | — |  | — |  | — |
Increase based on Incremental Fair Value of Options/SARs Modified during Applicable FY | — |  | — |  | — |
Total Adjustments | $ | (1,957,485) |  | $ | (14,564) |  | $ | (224,527) |
| 2022
Adjustments | Former CEO Christopher Oddleifson | Average non-CEO NEOs
Deduction for Change in the Actuarial Present Values reported under the “Change in Pension Value and Nonqualified Deferred Compensation Earnings” Column of the Summary Compensation Table for Applicable FY | $ | — |  | $ | — |
Increase for Service Cost and, if applicable, Prior Service Cost for Pension Plans | 397,084 |  | 22,880 |
Deduction for Amounts Reported under the “Stock Awards” and “Option Awards” Columns in the Summary Compensation Table for Applicable FY | (711,438) |  | (251,968) |
Increase based on ASC 718 Fair Value of Awards Granted during Applicable FY that Remain Unvested as of Applicable FY End, determined as of Applicable FY End | 993,698 |  | 350,966 |
Increase/deduction for Awards Granted during Prior FY that were Outstanding and Unvested as of Applicable FY End, determined based on change in ASC 718 Fair Value from Prior FY End to Applicable FY End | 63,357 |  | 18,830 |
Increase based on ASC 718 Fair Value of Awards Granted during Applicable FY that Vested during Applicable FY, determined as of Vesting Date | — |  | — |
Increase/deduction for Awards Granted during Prior FY that Vested During Applicable FY, determined based on change in ASC 718 Fair Value from Prior FY End to Vesting Date | 20,160 |  | 5,663 |
Deduction of ASC 718 Fair Value of Awards Granted during Prior FY that failed to meet the applicable vesting conditions during Applicable FY, determined as of Prior FY End | (240,853) |  | (60,213) |
Increase based on Dividends or Other Earnings Paid during Applicable FY prior to Vesting Date | — |  | — |
Increase based on Incremental Fair Value of Options/SARs Modified during Applicable FY | — |  | — |
Total Adjustments | $ | 522,008 |  | $ | 86,158 |
| 2021
Adjustments | Former CEO Christopher Oddleifson | Average non-CEO NEOs
Deduction for Change in the Actuarial Present Values reported under the “Change in Pension Value and Nonqualified Deferred Compensation Earnings” Column of the Summary Compensation Table for Applicable FY | $ | (155,087) |  | $ | (9,113) |
Increase for Service Cost and, if applicable, Prior Service Cost for Pension Plans | 449,226 |  | 55,598 |
Deduction for Amounts Reported under the “Stock Awards” and “Option Awards” Columns in the Summary Compensation Table for Applicable FY | (822,517) |  | (253,712) |
Increase based on ASC 718 Fair Value of Awards Granted during Applicable FY that Remain Unvested as of Applicable FY End, determined as of Applicable FY End | 926,671 |  | 285,758 |
Increase/deduction for Awards Granted during Prior FY that were Outstanding and Unvested as of Applicable FY End, determined based on change in ASC 718 Fair Value from Prior FY End to Applicable FY End | 193,722 |  | 55,349 |
Increase based on ASC 718 Fair Value of Awards Granted during Applicable FY that Vested during Applicable FY, determined as of Vesting Date | — |  | — |
Increase/deduction for Awards Granted during Prior FY that Vested During Applicable FY, determined based on change in ASC 718 Fair Value from Prior FY End to Vesting Date | 185,412 |  | 46,579 |
Deduction of ASC 718 Fair Value of Awards Granted during Prior FY that failed to meet the applicable vesting conditions during Applicable FY, determined as of Prior FY End | (67,264) |  | (16,274) |
Increase based on Dividends or Other Earnings Paid during Applicable FY prior to Vesting Date | — |  | — |
Increase based on Incremental Fair Value of Options/SARs Modified during Applicable FY | — |  | — |
Total Adjustments | $ | 710,163 |  | $ | 164,185 |
Compensation Actually Paid vs. Total Shareholder Return | The following table summarizes the relationship between CEO CAP and average Other NEO CAP versus the Company’s cumulative TSR and the relationship between the Company’s cumulative TSR and peer group cumulative TSR for each year presented: |  |  |
Compensation Actually Paid vs. Net Income | The following table summarizes the relationship between CEO CAP and average Other NEO CAP versus the Company’s net income for each year presented: |  |  |
Compensation Actually Paid vs. Company Selected Measure | The following table summarizes the relationship between CEO CAP and average Other NEO CAP versus the Company’s ROATCE for each year presented: |  |  |
Total Shareholder Return Vs Peer Group | The following table summarizes the relationship between CEO CAP and average Other NEO CAP versus the Company’s cumulative TSR and the relationship between the Company’s cumulative TSR and peer group cumulative TSR for each year presented: |  |  |
Tabular List, Table |
Tabular List of Most Important Financial Performance Measures
Return on average tangible common equity (Non-GAAP) (calculated by dividing net income by average tangible common equity)
Net operating earnings per share (Non-GAAP) (1) (net operating earnings calculated as net income less noncore items, such as merger and acquisition expenses)
Return on average assets (GAAP) (calculated by dividing net income by average assets)
Return on average common equity (GAAP) (calculated by dividing net income by average common equity)
Total Shareholder Return Amount | $ 89.11 | 109.82 | 103.36 | 90.38
Net Income (Loss) | $ 239,502,000 | $ 263,813,000 | $ 120,992,000 | $ 121,167,000
Company Selected Measure Amount | 0.1278 | 0.1387 | 0.0920 | 0.1038
Additional 402(v) Disclosure | (1) Please refer to the Company’s Annual Report on Form 10-K for a reconciliation of Net Operating Earnings to Net Income. |  |  |
indb_KBW NASDAQ Bank Index PeerGroupTotalShareholderRtnAmt | $ 96.65 | $ 97.52 | $ 124.06 | $ 89.69
indb_KBW NASDAQ Regional Banking Index PeerGroupTotalShareholderRtnAmt | $ 115.64 | 116.10 | 124.74 | 91.29
Measure:: 1 |  |  |  |
Pay vs Performance Disclosure |  |  |  |
Name | Return on average tangible common equity (Non-GAAP) (calculated by dividing net income by average tangible common equity) |  |  |
Measure:: 2 |  |  |  |
Pay vs Performance Disclosure |  |  |  |
Name | Net operating earnings per share (Non-GAAP) (1) (net operating earnings calculated as net income less noncore items, such as merger and acquisition expenses) |  |  |
Measure:: 3 |  |  |  |
Pay vs Performance Disclosure |  |  |  |
Name | Return on average assets (GAAP) (calculated by dividing net income by average assets) |  |  |
Measure:: 4 |  |  |  |
Pay vs Performance Disclosure |  |  |  |
Name | Return on average common equity (GAAP) (calculated by dividing net income by average common equity) |  |  |
INDB ChristopherOddleifsonMember [Member] |  |  |  |
Pay vs Performance Disclosure |  |  |  |
PEO Total Compensation Amount | $ 2,735,396 | 2,939,498 | 2,783,438 | 3,319,086
PEO Actually Paid Compensation Amount | 777,911 | 3,461,506 | 3,493,601 | 2,172,806
INDB JeffreyTengelMember [Member] |  |  |  |
Pay vs Performance Disclosure |  |  |  |
PEO Total Compensation Amount | 5,213,225 |  |  |
PEO Actually Paid Compensation Amount | 5,198,661 |  |  |
PEO | Adjustment, Value of Dividends and Other Earnings Paid [Member] |  |  |  |
Pay vs Performance Disclosure |  |  |  |
Adjustment to Compensation, Amount | 0 | 0 | 0 | 0
Non-PEO NEO |  |  |  |
Pay vs Performance Disclosure |  |  |  |
Adjustment to Compensation, Amount | (224,527) | 86,158 | 164,185 | (235,657)
Non-PEO NEO | Adjustment, Change in Actuarial Present Values of Pension [Member] |  |  |  |
Pay vs Performance Disclosure |  |  |  |
Adjustment to Compensation, Amount | (52,416) | 0 | (9,113) | (223,256)
Non-PEO NEO | Adjustment, Increase for Service Cost and Prior Service cost for Pensions [Member] |  |  |  |
Pay vs Performance Disclosure |  |  |  |
Adjustment to Compensation, Amount | 15,701 | 22,880 | 55,598 | 56,199
Non-PEO NEO | Adjustment, Deduction for Stock Awards and Option Awards [Member] |  |  |  |
Pay vs Performance Disclosure |  |  |  |
Adjustment to Compensation, Amount | (249,193) | (251,968) | (253,712) | (202,277)
Non-PEO NEO | Adjustment, Increase for Equity Awards Granted in Current Year, Unvested [Member] |  |  |  |
Pay vs Performance Disclosure |  |  |  |
Adjustment to Compensation, Amount | 249,699 | 350,966 | 285,758 | 227,830
Non-PEO NEO | Adjustment, Equity Awards Granted in Prior Years, Unvested [Member] |  |  |  |
Pay vs Performance Disclosure |  |  |  |
Adjustment to Compensation, Amount | (82,662) | 18,830 | 55,349 | (64,384)
Non-PEO NEO | Adjustment, Increase for Equity Awards Granted in Current Year, Vested [Member] |  |  |  |
Pay vs Performance Disclosure |  |  |  |
Adjustment to Compensation, Amount | 2,566 | 0 | 0 | 0
Non-PEO NEO | Adjustment, Equity Awards Granted in Prior Years, Vested [Member] |  |  |  |
Pay vs Performance Disclosure |  |  |  |
Adjustment to Compensation, Amount | (21,842) | 5,663 | 46,579 | (29,769)
Non-PEO NEO | Adjustment, Equity Awards Granted in Prior Years, Forfeited [Member] |  |  |  |
Pay vs Performance Disclosure |  |  |  |
Adjustment to Compensation, Amount | (86,380) | (60,213) | (16,274) | 0
Non-PEO NEO | Adjustment, Change in Fair Value of Awards Modified [Member] |  |  |  |
Pay vs Performance Disclosure |  |  |  |
Adjustment to Compensation, Amount | 0 | 0 | 0 | 0
INDB ChristopherOddleifsonMember [Member] |  |  |  |
Pay vs Performance Disclosure |  |  |  |
Adjustment to Compensation, Amount | (1,957,485) | 522,008 | 710,163 | (1,146,280)
INDB ChristopherOddleifsonMember [Member] | Adjustment, Change in Actuarial Present Values of Pension [Member] |  |  |  |
Pay vs Performance Disclosure |  |  |  |
Adjustment to Compensation, Amount | (804,577) | 0 | (155,087) | (1,291,254)
INDB ChristopherOddleifsonMember [Member] | Adjustment, Increase for Service Cost and Prior Service cost for Pensions [Member] |  |  |  |
Pay vs Performance Disclosure |  |  |  |
Adjustment to Compensation, Amount | 323,112 | 397,084 | 449,226 | 427,975
INDB ChristopherOddleifsonMember [Member] | Adjustment, Deduction for Stock Awards and Option Awards [Member] |  |  |  |
Pay vs Performance Disclosure |  |  |  |
Adjustment to Compensation, Amount | 0 | (711,438) | (822,517) | (664,774)
INDB ChristopherOddleifsonMember [Member] | Adjustment, Increase for Equity Awards Granted in Current Year, Unvested [Member] |  |  |  |
Pay vs Performance Disclosure |  |  |  |
Adjustment to Compensation, Amount | 0 | 993,698 | 926,671 | 748,584
INDB ChristopherOddleifsonMember [Member] | Adjustment, Equity Awards Granted in Prior Years, Unvested [Member] |  |  |  |
Pay vs Performance Disclosure |  |  |  |
Adjustment to Compensation, Amount | (159,002) | 63,357 | 193,722 | (245,840)
INDB ChristopherOddleifsonMember [Member] | Adjustment, Increase for Equity Awards Granted in Current Year, Vested [Member] |  |  |  |
Pay vs Performance Disclosure |  |  |  |
Adjustment to Compensation, Amount | 0 | 0 | 0 | 0
INDB ChristopherOddleifsonMember [Member] | Adjustment, Equity Awards Granted in Prior Years, Vested [Member] |  |  |  |
Pay vs Performance Disclosure |  |  |  |
Adjustment to Compensation, Amount | (153,164) | 20,160 | 185,412 | (120,971)
INDB ChristopherOddleifsonMember [Member] | Adjustment, Equity Awards Granted in Prior Years, Forfeited [Member] |  |  |  |
Pay vs Performance Disclosure |  |  |  |
Adjustment to Compensation, Amount | (1,163,854) | (240,853) | (67,264) | 0
INDB ChristopherOddleifsonMember [Member] | Adjustment, Value of Dividends and Other Earnings Paid [Member] |  |  |  |
Pay vs Performance Disclosure |  |  |  |
Adjustment to Compensation, Amount | 0 | 0 | 0 | 0
INDB ChristopherOddleifsonMember [Member] | Adjustment, Change in Fair Value of Awards Modified [Member] |  |  |  |
Pay vs Performance Disclosure |  |  |  |
Adjustment to Compensation, Amount | 0 | $ 0 | $ 0 | $ 0
INDB JeffreyTengelMember [Member] |  |  |  |
Pay vs Performance Disclosure |  |  |  |
Adjustment to Compensation, Amount | (14,564) |  |  |
INDB JeffreyTengelMember [Member] | Adjustment, Change in Actuarial Present Values of Pension [Member] |  |  |  |
Pay vs Performance Disclosure |  |  |  |
Adjustment to Compensation, Amount | 0 |  |  |
INDB JeffreyTengelMember [Member] | Adjustment, Increase for Service Cost and Prior Service cost for Pensions [Member] |  |  |  |
Pay vs Performance Disclosure |  |  |  |
Adjustment to Compensation, Amount | 0 |  |  |
INDB JeffreyTengelMember [Member] | Adjustment, Deduction for Stock Awards and Option Awards [Member] |  |  |  |
Pay vs Performance Disclosure |  |  |  |
Adjustment to Compensation, Amount | (2,008,786) |  |  |
INDB JeffreyTengelMember [Member] | Adjustment, Increase for Equity Awards Granted in Current Year, Unvested [Member] |  |  |  |
Pay vs Performance Disclosure |  |  |  |
Adjustment to Compensation, Amount | 1,994,222 |  |  |
INDB JeffreyTengelMember [Member] | Adjustment, Equity Awards Granted in Prior Years, Unvested [Member] |  |  |  |
Pay vs Performance Disclosure |  |  |  |
Adjustment to Compensation, Amount | 0 |  |  |
INDB JeffreyTengelMember [Member] | Adjustment, Increase for Equity Awards Granted in Current Year, Vested [Member] |  |  |  |
Pay vs Performance Disclosure |  |  |  |
Adjustment to Compensation, Amount | 0 |  |  |
INDB JeffreyTengelMember [Member] | Adjustment, Equity Awards Granted in Prior Years, Vested [Member] |  |  |  |
Pay vs Performance Disclosure |  |  |  |
Adjustment to Compensation, Amount | 0 |  |  |
INDB JeffreyTengelMember [Member] | Adjustment, Equity Awards Granted in Prior Years, Forfeited [Member] |  |  |  |
Pay vs Performance Disclosure |  |  |  |
Adjustment to Compensation, Amount | 0 |  |  |
INDB JeffreyTengelMember [Member] | Adjustment, Value of Dividends and Other Earnings Paid [Member] |  |  |  |
Pay vs Performance Disclosure |  |  |  |
Adjustment to Compensation, Amount | 0 |  |  |
INDB JeffreyTengelMember [Member] | Adjustment, Change in Fair Value of Awards Modified [Member] |  |  |  |
Pay vs Performance Disclosure |  |  |  |
Adjustment to Compensation, Amount | $ 0 |  |  |

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