Advances from Federal Home Loan Bank available.

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- Definition

Amount of subordinated debentures, assumed at the acquisition date.

+ References

No definition available.

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- Definition

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

+ References

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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- Definition

Amount of liabilities assumed at the acquisition date.

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- Definition

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

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- Definition

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

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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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No definition available.

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- Definition

Amount of the collateral pledged in support of federal home loan bank advances outstanding.

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- Definition

Amount of advances from Federal Home Loan Bank (FHLBank) 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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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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- Definition

The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

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Note 11 - Other Borrowings and Subordinated Debentures (Details Textual) - USD ($)	1 Months Ended	12 Months Ended
	Oct. 31, 2015	Dec. 31, 2017	Oct. 31, 2017	Oct. 19, 2017	May 15, 2017
Debt Instrument, Face Amount	$ 52,300,000
Debt Instrument, Interest Rate, Stated Percentage	3.85%
Debt Instrument, Term	10 years
Debt Instrument, Periodic Payment Terms, Balloon Payment Term	5 years
Repayments of Long-term Debt	$ 36,000,000
Federal Home Loan Bank, Advances, Maturities Summary, Due in Next Twelve Months		$ 1,100,000,000
Advances from Federal Home Loan Banks		1,300,000,000
Advances from Federal Home Loan Bank Available		2,258,000,000
Federal Home Loan Bank, Advances, General Debt Obligations, Disclosures, Collateral Pledged		$ 3,785,000,000
Federal Home Loan Bank Advances [Member]
Debt Instrument, Term		1 year
U.S. Bank National Association [Member] \| Revolving Credit Facility [Member]
Line of Credit Facility, Maximum Borrowing Capacity			$ 75,000,000
OKSB and First Texas Acquisitions [Member]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities				$ 75.90
Hardeman County Investment Company, Inc. [Member]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities					$ 419,656,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Subordinated Debentures					$ 6,702,000