Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount after tax of increase (decrease) to equity or (increase) decrease to net assets, resulting from the cumulative effect adjustment of a new accounting principle applied in the period of adoption.

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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Sum of the carrying amounts as of the date of the latest financial statement presented of securities which are owned but transferred to another party to serve as collateral to partially or fully secure a debt obligation, repurchase agreement or other current or potential obligation, and for which the transferee is not permitted to sell or re-pledge them to an unrelated party.

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Amount of unrealized gain (loss) recognized in the income statement on unsold other securities.

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Investments consist of high-risk collateralized mortgage obligations as defined by regulartory guidelines.

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Note 3 - Investment Securities (Details Textual) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018	Jan. 01, 2018	Dec. 31, 2017
Equity Securities, FV-NI	$ 1,797		$ 1,747	$ 1,800
Cumulative Effect of New Accounting Principle in Period of Adoption			(2,801)
Unrealized Gain (Loss) on Securities	50	$ (50)
High Risk Collateralized Mortgage Obligations	0		0
Debt Securities, Available-for-sale, Amortized Cost, Total	2,757,267		2,711,453
Debt Securities, Available-for-sale, Total	2,775,899		2,654,670
Other-than-temporary Impairment Loss, Debt Securities, Available-for-sale, Total	0
Pledged Financial Instruments, Not Separately Reported, Securities, Total	746,876		728,161
Debt Security, Corporate, US [Member]
Debt Securities, Available-for-sale, Amortized Cost, Total	1,379,704		1,337,608
Debt Securities, Available-for-sale, Total	1,395,047		1,315,041
Debt Security, Corporate, US [Member] \| External Credit Rating, Non Investment Grade [Member]
Debt Securities, Available-for-sale, Amortized Cost, Total	15,000
Debt Securities, Available-for-sale, Total	$ 14,200
Retained Earnings [Member]
Cumulative Effect of New Accounting Principle in Period of Adoption			$ (2,801)		$ (142)
Retained Earnings [Member] \| Accounting Standards Update 2016-01 [Member]
Cumulative Effect of New Accounting Principle in Period of Adoption				$ (142)