Income Taxes - Unrecognized Tax Benefits (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Sep. 30, 2013	Sep. 30, 2012
Income Tax Disclosure [Abstract]
Unrecognized income tax benefits beginning of year	$ 471	$ 542
Additions for tax positions of prior years	61	159
Reductions for tax positions of prior years	(103)
Tax examination and other settlements	(183)
Expirations of statute of limitations	(38)	(230)
Unrecognized income tax benefits at end of year	$ 208	$ 471

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The gross amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns as of the balance sheet date.

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The gross amount of decreases in unrecognized tax benefits resulting from tax positions taken in prior period tax returns, excluding amounts pertaining to examined tax returns.

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The gross amount of decreases in unrecognized tax benefits resulting from settlements with taxing authorities.

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The gross amount of increases in unrecognized tax benefits resulting from tax positions taken in prior period tax returns, excluding amounts pertaining to examined tax returns.

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The gross amount of decreases in unrecognized tax benefits resulting from lapses of the applicable statutes of limitations.

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