The floating interest rate, range of time period.

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Represents investment securities pledged as collateral.

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The total number of securities callable or non callable sold under agreement to repurchase.

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The total floating to fixed rate.

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The weighted average rate of securities sold under agreements.

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No definition available.

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- Definition

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

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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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Interest rate of advances made and reported by Federal Home Loan Bank (FHLBank).

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No definition available.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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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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Note 9 - Borrowed Funds (Details) - USD ($) $ in Thousands	3 Months Ended
Note 9 - Borrowed Funds (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Note 9 - Borrowed Funds (Details) [Line Items]
Securities Sold under Agreements to Repurchase (in Dollars)	$ 400,000	$ 400,000
Weighted Average Rate of Securities Sold Under Agreements	3.89%	3.89%
Advances from Federal Home Loan Banks (in Dollars)	$ 475,000	$ 275,000
Federal Home Loan Bank, Advances, Branch of FHLB Bank, Interest Rate	0.46%	1.13%
Floating to Fixed Rate Agreements Totaling $200 Million [Member]
Note 9 - Borrowed Funds (Details) [Line Items]
Number of Securities Sold Under Agreements to Repurchase	4
Total Floating to Fixed Rate (in Dollars)	$ 200,000
Debt, Weighted Average Interest Rate	5.00%
Floating Interest Rate, Range of Time Period	1 year
Securities Sold under Agreements to Repurchase [Member]
Note 9 - Borrowed Funds (Details) [Line Items]
Investment Securities Pledged As Collateral (in Dollars)	$ 429,000	$ 430,000
Mature in March 2018 [Member]
Note 9 - Borrowed Funds (Details) [Line Items]
Federal Home Loan Bank, Advances, Interest Rate			1.13%
Non Callable Fixed Rate Securities [Member]
Note 9 - Borrowed Funds (Details) [Line Items]
Weighted Average Rate of Securities Sold Under Agreements	4.00%
Number of Securities Sold Under Agreements to Repurchase	200,000,000	4
Debt, Weighted Average Interest Rate	2.78%	2.78%
Mature in August 2016 [Member] \| Non Callable Fixed Rate Securities [Member]
Note 9 - Borrowed Funds (Details) [Line Items]
Long-term Debt, Maturities, Repayments of Principal in Next Twelve Months (in Dollars)	$ 50,000
Mature in July 2017 [Member] \| Non Callable Fixed Rate Securities [Member]
Note 9 - Borrowed Funds (Details) [Line Items]
Long-term Debt, Maturities, Repayments of Principal in Year Two (in Dollars)	50,000
Mature in June 2018 [Member] \| Non Callable Fixed Rate Securities [Member]
Note 9 - Borrowed Funds (Details) [Line Items]
Long-term Debt, Maturities, Repayments of Principal in Year Three (in Dollars)	50,000
Mature in July 2018 [Member] \| Non Callable Fixed Rate Securities [Member]
Note 9 - Borrowed Funds (Details) [Line Items]
Long-term Debt, Maturities, Repayments of Principal in Year Four (in Dollars)	50,000
Over-night Borrowings [Member]
Note 9 - Borrowed Funds (Details) [Line Items]
Advances from Federal Home Loan Banks (in Dollars)	$ 100,000	$ 250,000
Federal Home Loan Bank, Advances, Branch of FHLB Bank, Interest Rate	0.48%	0.27%
At Fixed Rate [Member]
Note 9 - Borrowed Funds (Details) [Line Items]
Advances from Federal Home Loan Banks (in Dollars)	$ 375,000	$ 25,000
Mature in April 2016 [Member]
Note 9 - Borrowed Funds (Details) [Line Items]
Advances from Federal Home Loan Banks (in Dollars)	350,000
Mature in March 2018 [Member]
Note 9 - Borrowed Funds (Details) [Line Items]
Advances from Federal Home Loan Banks (in Dollars)	$ 25,000
Maximum [Member] \| Floating to Fixed Rate Agreements Totaling $200 Million [Member]
Note 9 - Borrowed Funds (Details) [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	5.07%
Maximum [Member] \| London Interbank Offered Rate (LIBOR) [Member] \| Floating to Fixed Rate Agreements Totaling $200 Million [Member]
Note 9 - Borrowed Funds (Details) [Line Items]
Debt Instrument, Basis Spread on Variable Rate	3.40%
Minimum [Member] \| Floating to Fixed Rate Agreements Totaling $200 Million [Member]
Note 9 - Borrowed Funds (Details) [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	4.89%