|
Auction Rate Securities - Additional Information (Detail) (USD $)
In Millions, unless otherwise specified |
3 Months Ended |
|---|---|
|
Sep. 30, 2013
|
|
| Schedule of Available-for-sale Securities [Line Items] | |
| Contractual maturities of ARS investment | Greater than five years |
| Auction Rate Securities with fair value maturing from 2015 to 2017 | $ 12.4 |
| Auction Rate Securities with fair value maturing from 2043 to 2045 | 3.1 |
| Auction rate securities with fair value having no stated maturity | 2.0 |
| ARS investments, investment grade | 5.5 |
| ARS investments, below investment grade | 18.5 |
|
Minimum [Member]
|
|
| Schedule of Available-for-sale Securities [Line Items] | |
| Maturity period one | 2015 |
| Maturity period two | 2043 |
|
Maximum [Member]
|
|
| Schedule of Available-for-sale Securities [Line Items] | |
| Maturity period one | 2017 |
| Maturity period two | 2045 |
|
Auction Rate Securities [Member]
|
|
| Schedule of Available-for-sale Securities [Line Items] | |
| ARS investments redeemed at par | $ 0 |