Minimum days past due for TDR loans to be classified as non-performing.

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- Definition

Represents the limit of loan above which loans are reviewed annually.

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No definition available.

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- Definition

Represents the limit of loan where loans are processed through an expedited underwriting process.

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No definition available.

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- Definition

Amount of loans increased (decrease) due to net accretable purchase accounting adjustments.

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No definition available.

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- Definition

Represents residential real estate loans that are in the process of foreclosure.

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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.

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No definition available.

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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
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-SubTopic 20
-Section 50
-Paragraph 1
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- Definition

Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

Number of financing receivables that have been modified by troubled debt restructurings.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
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Amount, after troubled debt restructuring, of modified financing receivable.

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- Definition

Number of financing receivable contracts modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953682-111524

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- Definition

Reflects the amount of additional interest income that would have been recorded if impaired or nonperforming loans were instead current, in compliance with their original terms, and outstanding throughout the reporting period or since origination (if held for part of the period).

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Portfolio loans - Narrative (Details)	3 Months Ended		9 Months Ended
Portfolio loans - Narrative (Details)	Sep. 30, 2019 USD ($) loan	Sep. 30, 2018 USD ($) loan	Sep. 30, 2019 USD ($) loan contract	Sep. 30, 2018 USD ($) loan	Dec. 31, 2018 USD ($)
Portfolio Loans
Net deferred loan origination costs	$ 5,400,000		$ 5,400,000		$ 5,600,000
Amount of loan reduction due to net accretable purchase accounting adjustments	22,500,000		22,500,000		$ 13,900,000
Gross interest income that would have been recorded if impaired loans had been current	500,000	$ 400,000	$ 1,600,000	$ 1,100,000
Loans classified as a TDR		$ 0
TDRs subsequently classified as non-performing and had payment defaults		0	1	0
Minimum days past due for TDR loans to be classified as non-performing			90 days
Balance of all acquired loans	1,700,000,000		$ 1,700,000,000
Commercial
Portfolio Loans
Loans classified as a TDR	$ 300,000		$ 300,000
Performing loans classified as TDRs \| loan	1		1
Commercial real estate
Portfolio Loans
Loans classified as a TDR			$ 3,200,000
Retail real estate
Portfolio Loans
Loans classified as a TDR				$ 100,000
Performing loans classified as TDRs \| loan				1
Loans in the process of foreclosure			3,100,000
Maximum \| Commercial real estate
Portfolio Loans
Limit where loans are processed through an expedited underwriting process			1,000,000.0
Pass and watch \| Commercial
Portfolio Loans
Limit where loans are processed through an expedited underwriting process			350,000
Pass and watch \| Minimum \| Commercial
Portfolio Loans
Limit where loans are processed through an expedited underwriting process			350,000
Pass and watch \| Maximum \| Commercial
Portfolio Loans
Limit where loans are processed through an expedited underwriting process			1,000,000.0
Watch \| Commercial
Portfolio Loans
Limit above which loans are annually reviewed			1,000,000.0
Special Mention
Portfolio Loans
Limit above which loans are annually reviewed			$ 350,000