Accrued interest rate on deferred bonus.

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Represents the amount of deferred bonus accrued in other liabilities.

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

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Represents the threshold for deferred bonus.

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Carrying value as of the balance sheet date of obligations incurred and payable for incentive compensation awarded to employees and directors or earned by them based on the terms of one or more relevant arrangements.

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Amount of borrowings as of the balance sheet date from the Federal Home Loan Bank, which are primarily used to cover shortages in the required reserve balance and liquidity shortages.

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Amount of the required periodic payments applied to principal.

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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average interest rate of debt outstanding.

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Discloses the single interest rate [if] applicable to the advances from the Federal Home Loan Bank, by branch, as of the Balance Sheet date.

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Amount of the cost of borrowed funds accounted for as interest expense for debt.

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Amount of interest expense classified as other.

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Carrying value as of the balance sheet date of long-term debt (with maturities initially due after one year or beyond the operating cycle if longer) identified as Junior Subordinated Notes, which have a lower priority than senior instruments, excluding current portion.

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

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Amount, after the effects of master netting arrangements, of funds outstanding borrowed in the form of a security repurchase agreement between the entity and another party for the sale and repurchase of identical or substantially the same securities at a date certain for a specified price. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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Note 8 - Borrowed Funds (Details Textual) - USD ($)							12 Months Ended
Note 8 - Borrowed Funds (Details Textual) - USD ($)	May 28, 2019	Nov. 14, 2017	Oct. 12, 2017	Nov. 23, 2014	Mar. 13, 2014	Nov. 23, 2004	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Securities Sold under Agreements to Repurchase, Total							$ 0	$ 0
Short-term Debt, Total							25,683,000	0
Advances from Federal Home Loan Banks, Total							670,000,000	530,000,000
Threshold for Deferred Bonus						$ 225,000
Amount of Deferred Bonus Accrued in Other Liabilities					$ 300,000	$ 610,000
Accrued Interest on Deferred Bonus	5.72%			5.06%	5.02%	7.00%
Interest Expense, Other							99,000	92,000	$ 87,000
Accrued Bonuses							2,000,000.0	1,900,000
Junior Subordinated Notes, Noncurrent							$ 119,100,000	$ 119,100,000
Junior Subordinated Debt [Member]
Debt Instrument, Interest Rate, Stated Percentage							4.09%	4.96%
Debt Instrument, Term							30 years
Interest Expense, Debt, Total							$ 5,600,000	$ 5,200,000	$ 4,100,000
SinoPac Bancorp [Member]
Payments to Acquire Businesses, Gross		$ 100,000,000
Over-night Borrowings [Member]
Advances from Federal Home Loan Banks, Total							$ 450,000,000.0	$ 200,000,000.0
Federal Home Loan Bank, Advances, Branch of FHLB Bank, Interest Rate							1.66%	2.56%
Non Overnight Borrowings [Member]
Advances from Federal Home Loan Banks, Total							$ 220,000,000	$ 330,000,000
Federal Home Loan Bank, Advances, Branch of FHLB Bank, Interest Rate							2.26%	2.42%
Short-term debt Through Hong Kong Office [Member]
Short-term Debt, Total							$ 25,700,000
Debt, Weighted Average Interest Rate							2.69%
Mature in May 2021 [Member]
Advances from Federal Home Loan Banks, Total							$ 75,000,000
Mature in June 2021 [Member]
Advances from Federal Home Loan Banks, Total							50,000,000
Mature in July 2021 [Member]
Advances from Federal Home Loan Banks, Total							75,000,000
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%
Mature in July 2020 [Member] \| SinoPac Bancorp [Member]
Business Combination, Deferred Payments							$ 7,000,000.0
Debt Instrument, Interest Rate, Stated Percentage							3.40%
Term Loan [Member] \| US Bank [Member]
Debt Instrument, Face Amount			$ 75,000,000.0					$ 70,300,000
Debt Instrument, Interest Rate, Effective Percentage								4.125%
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%
Ten-year Treasury Note [Member]
Debt Instrument, Basis Spread on Variable Rate				2.75%
Debt Instrument, Term				10 years
Five-year Treasury Note [Member]
Debt Instrument, Basis Spread on Variable Rate	3.50%
Debt Instrument, Term	5 years