Other Real Estate Owned (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Real Estate Properties [Line Items]
Advances from Federal Home Loan Banks			$ 175,200
Mortgage Loans in Process of Foreclosure, Amount	$ 23,900		$ 22,000
Total
Beginning balance	48,030	$ 51,097
Additions	3,133	6,582
Sales	(6,934)	(7,997)
Write-downs	(923)	(1,593)
Ending balance	43,306	$ 48,089
Mortgage
Total
Beginning balance	17,200
Ending balance	15,400
Federal Home Loan Bank of Chicago
Real Estate Properties [Line Items]
Advances from Federal Home Loan Banks	$ 14,500

Amount of borrowings as of the balance sheet date from the Federal Home Loan Bank, which are primarily used to cover shortages in the required reserve balance and liquidity shortages.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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-SubTopic 470
-Section 45
-Paragraph 1
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Recorded investment of consumer mortgage loan receivables secured by residential real estate properties for which formal foreclosure proceedings are in process.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 35
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Carrying amount of other real estate not separately disclosed, including, but not limited to, real estate investments, real estate loans that qualify as investments in real estate, and premises that are no longer used in operations may also be included in real estate owned. This does not include real estate assets taken in settlement of troubled loans through surrender or foreclosure.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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-SubTopic 210
-Section S99
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Valuation adjustments made to other real estate not separately disclosed, including, but not limited to, real estate investments, real estate loans that qualify as investments in real estate, and premises that are no longer used in operations may also be included in real estate owned. This excludes real estate assets taken in settlement of troubled loans through surrender or foreclosure.

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