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Investment securities pledged as collateral.

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Face (par) amount of debt instrument at time of issuance.

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Amount of the required periodic payments applied to principal.

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Note 10 - Borrowed Funds (Details Textual) - USD ($)		6 Months Ended
Note 10 - Borrowed Funds (Details Textual) - USD ($)	Oct. 12, 2017	Jun. 30, 2018	Dec. 31, 2017	Nov. 14, 2017
Securities Sold under Agreements to Repurchase, Total		$ 50,000,000	$ 100,000,000
Weighted Average Rate Of Securities Sold Under Agreements		2.98%	2.86%
Advances from Federal Home Loan Banks, Total		$ 480,000,000	$ 430,000,000
SinoPac Bancorp [Member]
Business Combination, Deferred Payments		$ 35,200,000		$ 35,400,000
Business Combination, Deferred Payments, Disbursed Rate, In Next Twelve Months		50.00%
Business Combination, Deferred Payments, Disbursed Rate, In Year Two		30.00%
Business Combination, Deferred Payments, Disbursed Rate, In Year Three		20.00%
Debt Instrument, Face Amount		$ 36,000,000	$ 35,200,000
Debt Instrument, Interest Rate, Effective Percentage		2.80%
Mature in July 2018 [Member]
Advances from Federal Home Loan Banks, Total		$ 245,000,000
Mature in October 2018 [Member]
Advances from Federal Home Loan Banks, Total		5,000,000
Mature in December 2019 [Member]
Advances from Federal Home Loan Banks, Total		50,000,000
Mature in May 2023 [Member]
Advances from Federal Home Loan Banks, Total		$ 20,000,000
Business Combination, Deferred Payments [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument, Basis Spread on Variable Rate		1.50%
Term Loan [Member] \| US Bank [Member]
Debt Instrument, Face Amount	$ 75,000,000
Debt Instrument, Interest Rate, Effective Percentage		3.75%	3.125%
Debt Instrument, Periodic Payment, Principal	$ 4,700,000
Term Loan [Member] \| London Interbank Offered Rate (LIBOR) [Member] \| US Bank [Member]
Debt Instrument, Basis Spread on Variable Rate	1.75%
Over-night Borrowings [Member]
Advances from Federal Home Loan Banks, Total		$ 160,000,000	$ 325,000,000
Federal Home Loan Bank, Advances, Branch of FHLB Bank, Interest Rate		2.08%	1.41%
Non Overnight Borrowings [Member]
Advances from Federal Home Loan Banks, Total		$ 320,000,000	$ 105,000,000
Federal Home Loan Bank, Advances, Branch of FHLB Bank, Interest Rate		1.78%	1.41%
Securities Sold under Agreements to Repurchase [Member]
Investment Securities Pledged As Collateral		$ 55,400,000	$ 108,400,000
Fixed Rate Non-callable Securities Sold Under Agreements to Repurchase [Member] \| Mature in June 2018 [Member]
Securities Sold under Agreements to Repurchase, Total		$ 50,000,000