Carrying Amount [Abstract]

No definition available.

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- Definition

The aggregate deficiency of a loan's cash flows expected to be collected over the investor's initial investment in the loan. This relates to loans with 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

No definition available.

+ Details

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- Definition

Contractual Payments at Acquisition [Abstract]

+ References

No definition available.

+ Details

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- Definition

For receivables acquired in a business combination, excluding certain loans and debt securities acquired in a transfer (as defined), this element represents the fair value of the receivables acquired, by major class of receivable, such as loans, direct finance leases (as defined), and any other class of receivables.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=73530397&loc=d3e4845-128472

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Balance Type:	debit
Period Type:	instant

- Definition

For receivables acquired in a business combination, excluding certain loans and debt securities acquired in a transfer (as defined), this element represents the gross contractual amounts receivable, by major class of receivable, such as loans, direct finance leases (as defined), and any other class of receivables.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)(2)
-URI http://asc.fasb.org/extlink&oid=73530397&loc=d3e4845-128472

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

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

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- 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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 15
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=27045933&loc=d3e13503-111538

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of cash flows expected to be collected at acquisition of acquired loans not accounted for as debt securities with evidence of deterioration of credit quality.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 15
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=27045933&loc=d3e13503-111538

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of expense related to loan loss not accounted for as debt securities, with evidence of deterioration of credit quality.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

A valuation allowance for financing receivables that are expected to be uncollectible.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953423-111524

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=65884687&loc=d3e4428-111522

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.7)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes loans held for sale. Excludes loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.7(a))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

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Balance Type:	debit
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- Definition

Net amount of the investment in a contractual right to receive money on demand or on fixed or determinable dates that is recognized as an asset in the creditor's statement of financial position. Examples include, but are not limited to, credit card receivables, notes receivable and receivables relating to lessor's rights to payments from leases other than operating leases that have been recorded as assets. Excludes trade accounts receivable with contractual maturity of one year or less and arose from the sale of goods or services.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.3)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Balance Type:	debit
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- Details

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- Details

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- Details

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Loans and Allowance for Loan Losses Loans and Allowance for Loan Losses (PCI Loans) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Sep. 08, 2016
Carrying Amount [Abstract]
Loans Receivable, Net	$ 1,939,501,000	$ 1,825,992,000
Loans and Leases Receivable, Net Amount	1,918,499,000	1,808,064,000
Contractual Payments at Acquisition [Abstract]
Financing Receivable, Net			$ 8,688,000
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Provision for Loan Losses	9,000	14,000
Receivables Acquired with Deteriorated Credit Quality [Member]
Carrying Amount [Abstract]
Loans Receivable, Net	259,000	8,086,000
Financing Receivable, Allowance for Credit Losses	9,000	14,000
Loans and Leases Receivable, Net Amount	250,000	8,072,000
Contractual Payments at Acquisition [Abstract]
Business Combination, Acquired Receivables, Gross Contractual Amount			10,650,000
Financing Receivable, Net	259,000	8,086,000
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Accretable Yield, Accretion	1,200,000
Certain Loans Acquired In A Transfer. Nonaccretable Difference			(1,962,000)
Certain Loans Acquired in Transfer Not Accounted for as Debt Securities, Acquired During Period, Cash Flows Expected to be Collected at Acquisition			8,688,000
Certain Loans Acquired in Transfer, Accretable Yield			0
Business Combination, Acquired Receivables, Fair Value			$ 8,688,000
1-4 Family residential properties
Carrying Amount [Abstract]
Loans Receivable, Net	293,667,000	326,415,000
1-4 Family residential properties \| Receivables Acquired with Deteriorated Credit Quality [Member]
Carrying Amount [Abstract]
Loans Receivable, Net	0	622,000
Multifamily residential properties
Carrying Amount [Abstract]
Loans Receivable, Net	61,798,000	83,200,000
Multifamily residential properties \| Receivables Acquired with Deteriorated Credit Quality [Member]
Carrying Amount [Abstract]
Loans Receivable, Net	0	1,011,000
Commercial real estate
Carrying Amount [Abstract]
Loans Receivable, Net	681,757,000	630,135,000
Commercial real estate \| Receivables Acquired with Deteriorated Credit Quality [Member]
Carrying Amount [Abstract]
Loans Receivable, Net	251,000	3,723,000
Loans secured by real estate
Carrying Amount [Abstract]
Loans Receivable, Net	1,271,999,000	1,214,962,000
Loans secured by real estate \| Receivables Acquired with Deteriorated Credit Quality [Member]
Carrying Amount [Abstract]
Loans Receivable, Net	251,000	5,356,000
Commercial and industrial loans
Carrying Amount [Abstract]
Loans Receivable, Net	444,263,000	409,033,000
Commercial and industrial loans \| Receivables Acquired with Deteriorated Credit Quality [Member]
Carrying Amount [Abstract]
Loans Receivable, Net	$ 8,000	$ 2,730,000