Purchased Loans (Details Textual)	3 Months Ended
Mar. 31, 2017 USD ($) loan	Mar. 31, 2016 USD ($) loan	Dec. 31, 2016 USD ($)
Loans and Allowance for Loan Losses (Textual) [Abstract]
Allowance for loan losses attributable to restructured loans	$ 42,923,000		$ 42,737,000
Purchased loans
Loans and Allowance for Loan Losses (Textual) [Abstract]
Number of restructured loans \| loan	2	0
Average recorded investment in impaired loans	$ 9,197,000	$ 2,333,000
Remaining availability under commitments to lend additional funds on restructured loans	1,245,000	0
Fair value of loans contractual principal cash flows amount	79,174,000
Fair value of loans contractual interest cash flows	16,000
Fair value of loans contractual interest payments	758,000
Fair value of loans contractual purchase discount	31,267,000
Purchased loans \| Nonaccruing Loans
Loans and Allowance for Loan Losses (Textual) [Abstract]
Outstanding balance of restructured loans	52,000
Purchased loans \| Restructured Loans
Loans and Allowance for Loan Losses (Textual) [Abstract]
Outstanding balance of restructured loans	1,201,000	5,041,000
Allowance for loan losses attributable to restructured loans	$ 31,000	$ 91,000

Fair value of loans contractual interest cash flows.

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Fair value of loans contractual principal cash flows amount.

+ References

No definition available.

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Fair value of loans contractual purchase discount.

+ References

No definition available.

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Fair value of loans future interest payments.

+ References

No definition available.

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Loans and the allowance for loan losses.

+ References

No definition available.

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- Definition

Number of Restructured Loans

+ References

No definition available.

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- Definition

Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5212-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5258-111524

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- Definition

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for 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 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953423-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
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-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953423-111524

Reference 3: 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(d))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-Publisher FASB
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-URI http://asc.fasb.org/extlink&oid=6379141&loc=d3e15032-111544

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- Definition

Reflects the unfunded portion of contractual agreements to lend funds to borrowers for loans whose terms have been modified by troubled debt restructuring.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=25495931&loc=d3e18794-111554

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- 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

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