Purchased Credit Impaired ("PCI") Loans - Rollforward of PCI Loans, Net of Allowance for Loan Losses (Details) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2019	Sep. 30, 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	$ 69,741
Acquisitions	68,183
Principal reductions and interest payments	(33,548)	(38,165)
Accretion of loan discount	8,014	5,118
Changes in contractual and expected cash flows due to remeasurement	12,633	10,101
Reductions due to disposals	(5,736)
Balance at end of period	94,766	46,795
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	112,710
Acquisitions	111,963
Principal reductions and interest payments	(33,548)	(38,165)
Accretion of loan discount	0	0
Changes in contractual and expected cash flows due to remeasurement	10,490	4,341
Reductions due to disposals	(9,121)
Balance at end of period	152,941	78,886
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	29,005
Acquisitions	13,542
Principal reductions and interest payments	0	0
Accretion of loan discount	0	0
Changes in contractual and expected cash flows due to remeasurement	(2,057)	(8,939)
Reductions due to disposals	(3,345)
Balance at end of period	23,439	20,066
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	13,964
Acquisitions	30,238
Principal reductions and interest payments	0	0
Accretion of loan discount	8,014	5,118
Changes in contractual and expected cash flows due to remeasurement	(86)	3,179
Reductions due to disposals	(40)
Balance at end of period	$ 34,736	$ 12,025

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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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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-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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