Interest-bearing time deposits in banks.

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- Definition

Interest Bearing Time Deposits In Banks And Securities [Line Items]

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- Definition

Percentage of investment portfolio guaranteed by permanent school fund.

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No definition available.

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- Definition

This item represents the gross profit realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

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-Publisher FASB
-Name Accounting Standards Codification
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This item represents the gross loss realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities.

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- Definition

Number of investment positions in available-for-sale investments in a continuous unrealized loss position for which an other-than-temporary impairment (OTTI) has not been recognized in the income statement.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Amount after other than temporary impairment (OTTI) accretion, of investments in debt securities classified as held-to-maturity.

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

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The cash inflow associated with the sale of debt securities classified as available-for-sale securities.

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The fair value of trading securities that serve as collateral for borrowings.

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Interest-bearing Time Deposits in Banks and Securities - Additional Information (Detail) $ in Thousands		3 Months Ended
	Mar. 31, 2018 USD ($) Investment	Mar. 31, 2018 USD ($) Investment	Mar. 31, 2017 USD ($)	Dec. 31, 2017 USD ($)
Interest Bearing Time Deposits In Banks And Securities [Line Items]
INTEREST-BEARING TIME DEPOSITS IN BANKS	$ 1,458	$ 1,458	$ 1,707	$ 1,458
Held-to-maturity securities	$ 0	$ 0	114	$ 0
Number of investment positions \| Investment	484	484
Securities pledged as collateral	$ 2,026,719	$ 2,026,719
Sales of investment securities available-for-sale		91,445	6,180
Gross realized gains from security sales		1,242	5
Gross realized losses from security sales or calls		$ 21	$ 2
Obligations of States and Political Subdivisions [Member] \| Texas [Member]
Interest Bearing Time Deposits In Banks And Securities [Line Items]
Percentage of securities guaranteed by Texas Permanent School Fund	28.97%
Obligations of States and Political Subdivisions [Member] \| Texas [Member] \| Available-for-Sale Securities [Member] \| Geographic Concentration Risk [Member]
Interest Bearing Time Deposits In Banks And Securities [Line Items]
Concentration risk, percentage	82.61%
Minimum [Member]
Interest Bearing Time Deposits In Banks And Securities [Line Items]
Interest-bearing time deposits, maturity period, years		1 year
Maximum [Member]
Interest Bearing Time Deposits In Banks And Securities [Line Items]
Interest-bearing time deposits, maturity period, years		2 years