Loans and Leases - Summary of Acquired PCI Loans (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Jun. 30, 2019	Dec. 31, 2018	Jun. 30, 2018	Dec. 31, 2017
Receivables [Abstract]
PCI Balance	$ 293,713	$ 4,802	$ 293,713	$ 4,802	$ 2,273	$ 3,816	$ 7,033	$ 11,844
Certain Loans Acquired in Transfer Accounted for as Debt Securities, Accretable Yield Movement Schedule [Roll Forward]
Balance, beginning of period	401	439	961	1,051
Addition attributable to the Merger	39,733	0	39,733	0
Accretion recognized in interest income	(4,312)	(38)	(5,015)	(188)
Net reclassification (to) from nonaccretable difference	(517)	0	179	370
Payments received	(824)	26	(1,377)	(806)
Balance, end of period	$ 34,481	$ 427	$ 34,481	$ 427

Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield, Payments

No definition available.

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- Definition

The aggregate excess of a loan's cash flows expected to be collected over the investor's initial investment in the loan for loans 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.

+ 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
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-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

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

+ References

No definition available.

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- Definition

The recorded balance, net of any applicable reductions (for example, unamortized accretable yield and other-than-temporary impairments), for loans 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.

+ 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
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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 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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- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 30
-Section 50
-Paragraph 2
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- References

No definition available.

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