Interest-bearing time deposits in banks.

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- Definition

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

+ References

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- Definition

Percentage of investment portfolio guaranteed by permanent school fund.

+ References

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 9
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- Definition

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

+ References

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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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-Publisher SEC
-Name Industry Guide
-Number 3
-Section V
-Paragraph D-E

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

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- Definition

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		9 Months Ended
	Sep. 30, 2017 USD ($) Investment	Sep. 30, 2017 USD ($) Investment	Sep. 30, 2016 USD ($)	Sep. 30, 2017 USD ($) Investment	Sep. 30, 2016 USD ($)	Dec. 31, 2016 USD ($)
Interest Bearing Time Deposits In Banks And Securities [Line Items]
INTEREST-BEARING TIME DEPOSITS IN BANKS	$ 1,458	$ 1,458	$ 1,707	$ 1,458	$ 1,707	$ 1,707
Held-to-maturity securities	$ 0	$ 0	129	$ 0	129	$ 121
Number of investment positions \| Investment	179	179		179
Securities pledged as collateral	$ 1,787,958	$ 1,787,958		$ 1,787,958
Sales of investment securities available-for-sale		83,605	7,410	120,576	20,792
Gross realized gains from security sales		1,750	239	2,550	1,158
Gross realized losses from security sales or calls		$ 675	$ 0	$ 725	$ 5
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	31.16%
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	82.70%
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