Investments of Insurance Subsidiaries - Additional Information (Detail) - Jun. 30, 2015 - USD ($) $ in Millions	Total
Amortized Cost and Fair Value Debt Securities [Abstract]
Amounts classified as current assets	$ 25
Available for sale securities expected maturity of debt securities	3 years 10 months 24 days
Available for sale securities average scheduled maturity	5 years 6 months

Available for sale securities expected maturity of debt securities (in years).

No definition available.

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