Note 4 - Acquisition (Details Textual) - SinoPac Bancorp [Member] - USD ($)				6 Months Ended
Dec. 12, 2017	Nov. 14, 2017	Jul. 14, 2017	Jun. 30, 2018
Business Combination, Aggregate Purchase Price			$ 351,600,000
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares			926,192
Payments to Acquire Businesses, Gross		$ 100,000,000	$ 284,984,000
Business Combination, Deferred Payments		$ 35,400,000		$ 35,200,000
Business Combination, Addition Cash Consideration Related to Realized Gain from Sale of Building	$ 4,100,000
Business Combination, Purchase Price Adjustments				$ 340,000

The addition cash consideration was paid based on the realized gain from the sale of the building.

No definition available.

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- Definition

Represents the amount of aggregate purchase price in a business combination.

+ References

No definition available.

+ Details

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- Definition

The amount of liabilities payable to a counter party pertain to a business combination.

+ References

No definition available.

+ Details

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- Definition

Represents the amount of purchase price adjustments in a business acquisition transaction.

+ References

No definition available.

+ Details

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- Definition

Number of shares of equity interests issued or issuable to acquire entity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)(4)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

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- Definition

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3213-108585

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