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Changes in Cost Basis and Fair Value of Auction Rate Securities (Detail) (USD $)
In Thousands, unless otherwise specified |
6 Months Ended | |||
|---|---|---|---|---|
|
Apr. 30, 2012
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Oct. 31, 2011
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Apr. 30, 2012
Cost Basis
Auction Rate Securities
|
Apr. 30, 2012
Fair Value, Inputs, Level 3
Auction Rate Securities
|
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| Schedule of Available-for-sale Securities [Line Items] | ||||
| Balance at beginning of year | $ 17,994 | $ 15,670 | $ 18,307 | $ 15,670 |
| Unrealized gains included in accumulated other comprehensive loss | 2,324 | |||
| Other-than-temporary credit losses recognized in earnings | (313) | |||
| Balance at ending of year | $ 17,994 | $ 15,670 | $ 17,994 | $ 17,994 |