Investments - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
Investments Debt And Equity Securities [Abstract]
Restricted investments	$ 14,685	$ 14,685
Investments in continuous unrealized loss position	$ 0	$ 0

Available For Sale Securities Continuous Unrealized Loss Position Twelve Months Or Longer Aggregate Losses Accumulated In Investments

No definition available.

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