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Investments - Additional Information (Detail) - Maximum [Member]	6 Months Ended
	Jun. 30, 2015
Schedule of Available-for-sale Securities [Line Items]
Investment securities maturity period or average life	3 years
Average duration of portfolio	1 year

X

- Definition

Investment Securities Maturity Period

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X

- Definition

Weighted Average Duration Investment Securities Portfolio

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X

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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