Gross Unrealized Losses (Detail) (Less than 80% of amortized cost, USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jun. 30, 2014
Gain (Loss) on Investments [Line Items]
Gross unrealized loss	$ 465
3-6 months
Gain (Loss) on Investments [Line Items]
Gross unrealized loss	465
Equity Securities
Gain (Loss) on Investments [Line Items]
Gross unrealized loss	465
Equity Securities | 3-6 months
Gain (Loss) on Investments [Line Items]
Gross unrealized loss	$ 465