Note 2 - Business Combinations - Fair Value of Assets and Liabilities Acquired (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
	Jul. 14, 2017	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Liabilities assumed:
Gains on bargain purchase		$ 5,440		$ 5,440
SinoPac Bancorp [Member]
Assets acquired:
Cash and cash equivalents	$ 166,932
Short-term investments	122,000
Securities available-for-sale	107,934
Loans	703,787
Premises and equipment	6,198
Cash surrender value of life insurance	46,083
Deferred tax assets, net	40,136
Core deposit intangible	7,144
Accrued interest receivable and other assets	9,134
Total assets acquired	1,209,348
Liabilities assumed:
Deposits	813,888
Long-term debt	30,000
Accrued interest payable and other liabilities	5,608
Total liabilities assumed	849,496
Net assets acquired	359,852
Cash paid	181,241
Fair value of common stock issued	34,862
Total consideration paid	216,103
Purchase price payable to SinoPac	138,309
Total consideration	354,412
Gains on bargain purchase	$ 5,440