Business Acquisition, Cost of Acquired Entity, Percentage Cash Paid

No definition available.

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- Definition

Business Acquisition, Cost of Acquired Entity, Percentage Stock Consideration

+ References

No definition available.

+ Details

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- Definition

Business Acquisition, Equity Interest Issued or Issuable, Number of Shares of Company Stock Issued for Each Share of Acquiree Stock

+ References

No definition available.

+ Details

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- Definition

Business Acquisition, Equity Interest Issued or Issuable, Per Share Value of Shares of Company Stock Issued for Each Share of Acquiree Stock

+ References

No definition available.

+ Details

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- Definition

Business Acquisition, Equity Interest Issued or Issuable Shareholders Option To Receive, Cash Per Share

+ References

No definition available.

+ Details

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- Definition

The total cost of the acquired entity including the cash paid to shareholders of acquired entities, fair value of debt and equity securities issued to shareholders of acquired entities, the fair value of the liabilities assumed, and direct costs of the acquisition.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Business Combination, Increase in Acquirer Outstanding Shares

+ References

No definition available.

+ Details

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- Definition

Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Loans Net

+ References

No definition available.

+ Details

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- Definition

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.

+ References

No definition available.

+ Details

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- References

No definition available.

+ Details

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- Definition

Fair value of acquired receivable from business combination, excluding certain loans and debt securities acquired in transfer.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=116869197&loc=d3e4845-128472

+ Details

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Period Type:	instant

- Definition

This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 23
-URI http://asc.fasb.org/extlink&oid=116868678&loc=d3e1043-128460

+ Details

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- Definition

Amount of equity interests of the acquirer, including instruments or interests issued or issuable in consideration for the business combination.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=116859721&loc=d3e6613-128477

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=116859721&loc=d3e6578-128477

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3213-108585

+ Details

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- Definition

Price of a single share of a number of saleable stocks of a company.

+ References

No definition available.

+ Details

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- Details

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- Details

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- Details

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ACQUISITIONS (Details Textual) - USD ($) $ / shares in Units, $ in Thousands			3 Months Ended								12 Months Ended
	Apr. 01, 2019	Nov. 16, 2018	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Business Acquisition [Line Items]
Acquisition Related Costs			$ 0	$ 705	$ 24,696	$ 1,032	$ 8,046	$ 2,688	$ 434	$ 0	$ 26,433	$ 11,168	$ 3,393
Business Combination, Pro Forma Information [Abstract]
Business Combination, Acquired Receivable, Fair Value	$ 23,200
Blue Hills Bancorp, Inc. [Member]
Business Acquisition [Line Items]
Equity Interest Issued or Issuable Shareholders Option To Receive, Cash Per Share	$ 5.25
Number of shares of company stock issued for each share of Central common stock (in shares)	0.2308
Business transaction value	$ 661,300
Cost of acquired entity, cash paid	$ 161,600
Increase in acquirer outstanding shares	6,166,010
Acquisition Related Costs											26,000
Loans acquired	$ 2,073,714
Combination of INDB and Blue Hills Bancorp, Inc. [Member]
Business Acquisition [Line Items]
Acquisition Related Costs											$ 57,300
MNB Bancorp [Member]
Business Acquisition [Line Items]
Equity Interest Issued or Issuable Shareholders Option To Receive, Cash Per Share		$ 275
Number of shares of company stock issued for each share of Central common stock (in shares)		3.55
Value of shares of company stock issued for each share of acquiree stock (in dollars per share)		$ 285.38
Company's closing price per share (in dollars per share)		$ 80.39
Business transaction value		$ 56,100
Cost of acquired entity, percentage cash		25.00%
Business Acquisition, Cost of Acquired Entity, Percentage Stock Consideration		75.00%
Cost of acquired entity, cash paid		$ 13,600
Consideration Transferred, Equity Interests Issued and Issuable		$ 42,500
Increase in acquirer outstanding shares		528,353
Acquisition Related Costs			$ 8,800
Loans acquired		$ 293,498
Combination of INDB and MNB Bancorp [Member]
Business Acquisition [Line Items]
Acquisition Related Costs												$ 7,500