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Loans and Allowance for Loan Losses - Purchased Credit-Impaired Loans (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
PCI Loans, Carrying Value [Abstract]
Unpaid principal balance	$ 3,323		$ 3,350
Carrying value	2,937		2,920
Accretable Yield [Roll Forward]
Balance at beginning of period	1,476	$ 2,618
Additions	0	0
Removals	0	(778)
Accretion	(90)	(98)
Reclassifications from nonaccretable difference	0	0
Balance at end of period	1,386	$ 1,742
Commercial loans | Commercial and industrial
PCI Loans, Carrying Value [Abstract]
Unpaid principal balance	42		45
Carrying value	41		40
Commercial real estate loans | Commercial real estate, owner-occupied
PCI Loans, Carrying Value [Abstract]
Unpaid principal balance	1,332		1,344
Carrying value	1,093		1,072
Commercial real estate loans | Commercial real estate, investor
PCI Loans, Carrying Value [Abstract]
Unpaid principal balance	1,702		1,713
Carrying value	1,700		1,706
Residential loans | Home equity
PCI Loans, Carrying Value [Abstract]
Unpaid principal balance	247		248
Carrying value	$ 103		$ 102

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Amount of the excess of a loan's cash flows expected to be collected over the investor's initial investment in acquired loans not accounted for as debt securities with evidence of deterioration of credit quality.

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-Publisher FASB
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Amount of accretion recognized for the excess of a loan's cash flows expected to be collected over the investor's initial investment in acquired loans not accounted for as debt securities, with evidence of deterioration of credit quality.

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Amount of additions to the excess of a loan's cash flows expected to be collected over the investor's initial investment in acquired loans not accounted for as debt securities with evidence of deterioration of credit quality.

+ References

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Amount of reduction, resulting from a sale or transfer of a loan, in the excess of a loan's cash flows expected to be collected over the investor's initial investment in acquired loans not accounted for as debt securities with evidence of deterioration of credit quality.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of reclassification (to) from nonaccretable difference (from) to the excess of a loan's cash flows expected to be collected over the investor's initial investment in acquired loans not accounted for as debt securities with evidence of deterioration of credit quality.

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The undiscounted sum of all amounts, including amounts deemed principal, interest, fees, penalties, and other under the loan, owed to the investor at the reporting date, whether or not currently due and whether or not any such amounts have been written or charged off by the investor. This relates to loans not accounted for as debt securities, with evidence of deterioration of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable.

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