Allowance for Loan Losses [Abstract]

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- Definition

Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953423-111524

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=118955202&loc=SL82895884-210446

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=119407570&loc=SL82919249-210447

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(7)(d))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=119407570&loc=SL82919249-210447

+ Details

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- Definition

The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

+ References

+ Details

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- Definition

Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

+ References

+ Details

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- Definition

The balance of financing receivables that were collectively evaluated for impairment.

+ References

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- Definition

The balance of financing receivables that were individually evaluated for impairment.

+ References

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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.

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- Definition

Amount, before allowance for credit loss, of financing receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=119407570&loc=SL82919230-210447

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Loans Receivable and the Allowance for Credit Losses - Allowance for Loan Losses Based on Evaluation Method (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Jan. 01, 2020	Dec. 31, 2019	Mar. 31, 2019	Dec. 31, 2018
Loans and Leases Receivable Disclosure [Line Items]
Individually evaluated for impairment	$ 38,529		$ 33,495
Collectively evaluated for impairment	3,387,233		3,395,220
Loans, gross	3,425,762		3,451,266
Allowance for Loan Losses [Abstract]
Loans receivable, allowance for credit losses, individually evaluated for impairment	3,925		3,663
Loans receivable, allowance for credit losses, collectively evaluated for impairment	47,262		24,166
Allowance for credit losses on loans	51,187	$ 29,079	29,079	$ 29,652	$ 29,307
Purchased credit impaired loans
Loans and Leases Receivable Disclosure [Line Items]
Loans, gross			22,551
Allowance for Loan Losses [Abstract]
Allowance for credit losses on loans			1,250
Agricultural
Loans and Leases Receivable Disclosure [Line Items]
Individually evaluated for impairment	3,256		4,312
Collectively evaluated for impairment	142,179		135,246
Loans, gross	145,435		140,446
Allowance for Loan Losses [Abstract]
Loans receivable, allowance for credit losses, individually evaluated for impairment	251		212
Loans receivable, allowance for credit losses, collectively evaluated for impairment	895		3,536
Allowance for credit losses on loans	1,146	3,748	3,748	3,691	3,637
Agricultural \| Purchased credit impaired loans
Loans and Leases Receivable Disclosure [Line Items]
Loans, gross			888
Allowance for Loan Losses [Abstract]
Allowance for credit losses on loans			0
Commercial and industrial
Loans and Leases Receivable Disclosure [Line Items]
Individually evaluated for impairment	10,778		12,242
Collectively evaluated for impairment	853,924		822,939
Loans, gross	864,702		835,236
Allowance for Loan Losses [Abstract]
Loans receivable, allowance for credit losses, individually evaluated for impairment	1,920		2,198
Loans receivable, allowance for credit losses, collectively evaluated for impairment	17,389		6,194
Allowance for credit losses on loans	19,309	8,394	8,394	7,594	7,478
Commercial and industrial \| Purchased credit impaired loans
Loans and Leases Receivable Disclosure [Line Items]
Loans, gross			55
Allowance for Loan Losses [Abstract]
Allowance for credit losses on loans			2
Commercial real estate
Loans and Leases Receivable Disclosure [Line Items]
Individually evaluated for impairment	23,764		16,082
Collectively evaluated for impairment	1,756,682		1,781,306
Loans, gross	1,780,446		1,814,859
Allowance for Loan Losses [Abstract]
Loans receivable, allowance for credit losses, individually evaluated for impairment	1,651		1,180
Loans receivable, allowance for credit losses, collectively evaluated for impairment	21,487		11,836
Allowance for credit losses on loans	23,138	13,804	13,804	14,798	15,635
Commercial real estate \| Purchased credit impaired loans
Loans and Leases Receivable Disclosure [Line Items]
Loans, gross			17,471
Allowance for Loan Losses [Abstract]
Allowance for credit losses on loans			788
Residential real estate
Loans and Leases Receivable Disclosure [Line Items]
Individually evaluated for impairment	710		838
Collectively evaluated for impairment	553,580		572,865
Loans, gross	554,290		577,799
Allowance for Loan Losses [Abstract]
Loans receivable, allowance for credit losses, individually evaluated for impairment	103		73
Loans receivable, allowance for credit losses, collectively evaluated for impairment	6,322		2,152
Allowance for credit losses on loans	6,425	2,685	2,685	3,272	2,349
Residential real estate \| Purchased credit impaired loans
Loans and Leases Receivable Disclosure [Line Items]
Loans, gross			4,096
Allowance for Loan Losses [Abstract]
Allowance for credit losses on loans			460
Consumer
Loans and Leases Receivable Disclosure [Line Items]
Individually evaluated for impairment	21		21
Collectively evaluated for impairment	80,868		82,864
Loans, gross	80,889		82,926
Allowance for Loan Losses [Abstract]
Loans receivable, allowance for credit losses, collectively evaluated for impairment	1,169		448
Allowance for credit losses on loans	$ 1,169	$ 448	448	$ 297	$ 208
Consumer \| Purchased credit impaired loans
Loans and Leases Receivable Disclosure [Line Items]
Loans, gross			41
Allowance for Loan Losses [Abstract]
Allowance for credit losses on loans			$ 0