Purchased Credit Impaired ("PCI") Loans - Rollforward of PCI Loans, Net of Allowance for Loan Losses (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield Movement Schedule [Roll Forward]
Balance at beginning of period	$ 45,220	$ 69,743
Acquisitions	68,184
Principal reductions and interest payments	(42,862)	(45,668)
Accretion of loan discount	10,345	6,654
Changes in contractual and expected cash flows due to remeasurement	14,601	14,491
Reductions due to disposals	(5,920)
Balance at end of period	89,568	45,220
Contractual Cashflows
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield Movement Schedule [Roll Forward]
Balance at beginning of period	73,157	112,711
Acquisitions	111,963
Principal reductions and interest payments	(42,862)	(45,668)
Accretion of loan discount	0	0
Changes in contractual and expected cash flows due to remeasurement	13,247	6,114
Reductions due to disposals	(9,626)
Balance at end of period	145,879	73,157
Non-accretable Difference
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield Movement Schedule [Roll Forward]
Balance at beginning of period	15,299	29,006
Acquisitions	13,541
Principal reductions and interest payments	0	0
Accretion of loan discount	0	0
Changes in contractual and expected cash flows due to remeasurement	357	(13,707)
Reductions due to disposals	(3,668)
Balance at end of period	25,529	15,299
Accretable Yield
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield Movement Schedule [Roll Forward]
Balance at beginning of period	12,638	13,962
Acquisitions	30,238
Principal reductions and interest payments	0	0
Accretion of loan discount	10,345	6,654
Changes in contractual and expected cash flows due to remeasurement	(1,711)	5,330
Reductions due to disposals	(38)
Balance at end of period	$ 30,782	$ 12,638

Acquisitions

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- Definition

Principal reductions and interest payments

+ References

No definition available.

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- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 15
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=118938799&loc=d3e13503-111538

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=118939070&loc=d3e15032-111544

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- Definition

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.

+ References

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- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=118939070&loc=d3e15032-111544

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 15
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=118938799&loc=d3e13503-111538

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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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