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.

No definition available.

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- Definition

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-SubTopic 210
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- Definition

Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

+ References

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- Definition

Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Accounting for Certain Loans Acquired in a Transfer - Amounts of Loans (Detail) - USD ($) $ in Thousands	Sep. 30, 2018	Jun. 30, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Dec. 31, 2016
Accounts, Notes, Loans and Financing Receivable [Line Items]
Outstanding balance	$ 2,957,386		$ 2,831,995
Allowance for loan losses	17,798	$ 17,071	16,394	$ 15,586	$ 15,027	$ 14,837
Carrying Amount	2,943,683		2,821,894
Loans Purchased With Evidence of Credit Deterioration [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Outstanding balance	18,351		29,863
Allowance for loan losses	121
Carrying Amount	18,230		29,863
Loans Purchased With Evidence of Credit Deterioration [Member] \| Commercial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Outstanding balance	16,298		27,198
Loans Purchased With Evidence of Credit Deterioration [Member] \| Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Outstanding balance	2,024		2,632
Loans Purchased With Evidence of Credit Deterioration [Member] \| Consumer [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Outstanding balance	29		33
Loans Purchased With Evidence of Credit Deterioration [Member] \| Heartland [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Outstanding balance	427		619
Carrying Amount	427		619
Loans Purchased With Evidence of Credit Deterioration [Member] \| Heartland [Member] \| Commercial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Outstanding balance	242		390
Loans Purchased With Evidence of Credit Deterioration [Member] \| Heartland [Member] \| Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Outstanding balance	185		229
Loans Purchased With Evidence of Credit Deterioration [Member] \| Summit [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Outstanding balance	2,038		4,523
Carrying Amount	2,038		4,523
Loans Purchased With Evidence of Credit Deterioration [Member] \| Summit [Member] \| Commercial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Outstanding balance	1,463		3,653
Loans Purchased With Evidence of Credit Deterioration [Member] \| Summit [Member] \| Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Outstanding balance	575		870
Loans Purchased With Evidence of Credit Deterioration [Member] \| Peoples Bancorp Inc [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Outstanding balance	383		441
Carrying Amount	383		441
Loans Purchased With Evidence of Credit Deterioration [Member] \| Peoples Bancorp Inc [Member] \| Commercial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Outstanding balance	280		315
Loans Purchased With Evidence of Credit Deterioration [Member] \| Peoples Bancorp Inc [Member] \| Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Outstanding balance	103		126
Loans Purchased With Evidence of Credit Deterioration [Member] \| Kosciusko Financial Inc [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Outstanding balance	968		1,241
Carrying Amount	968		1,241
Loans Purchased With Evidence of Credit Deterioration [Member] \| Kosciusko Financial Inc [Member] \| Commercial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Outstanding balance	769		838
Loans Purchased With Evidence of Credit Deterioration [Member] \| Kosciusko Financial Inc [Member] \| Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Outstanding balance	199		403
Loans Purchased With Evidence of Credit Deterioration [Member] \| LaPorte Bancorp Inc [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Outstanding balance	1,802		2,071
Allowance for loan losses	106
Carrying Amount	1,696		2,071
Loans Purchased With Evidence of Credit Deterioration [Member] \| LaPorte Bancorp Inc [Member] \| Commercial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Outstanding balance	811		1,034
Loans Purchased With Evidence of Credit Deterioration [Member] \| LaPorte Bancorp Inc [Member] \| Real Estate [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Outstanding balance	962		1,004
Loans Purchased With Evidence of Credit Deterioration [Member] \| LaPorte Bancorp Inc [Member] \| Consumer [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Outstanding balance	29		33
Loans Purchased With Evidence of Credit Deterioration [Member] \| Lafayette Community Bancorp [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Outstanding balance	3,245		4,271
Allowance for loan losses	15
Carrying Amount	3,230		4,271
Loans Purchased With Evidence of Credit Deterioration [Member] \| Lafayette Community Bancorp [Member] \| Commercial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Outstanding balance	3,245		4,271
Loans Purchased With Evidence of Credit Deterioration [Member] \| Wolverine Bancorp Inc [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Outstanding balance	9,488		16,697
Carrying Amount	9,488		16,697
Loans Purchased With Evidence of Credit Deterioration [Member] \| Wolverine Bancorp Inc [Member] \| Commercial [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Outstanding balance	$ 9,488		$ 16,697