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Investments and Fair Value Measurements - Schedule of Investments (Detail) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Schedule of Held-to-maturity Securities [Line Items]
Held-to-Maturity debt instruments	$ 23,651	$ 13,990
Federal Agency [Member]
Schedule of Held-to-maturity Securities [Line Items]
Held-to-Maturity debt instruments	$ 23,651	$ 13,990

X

- Definition

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

+ References

No definition available.

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- 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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Namespace Prefix:	us-gaap_
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- Details

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Namespace Prefix:
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Balance Type:
Period Type: