Available for Sale Securities by Original Contractual Maturity (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Schedule of Available-for-sale Securities [Line Items]
One year or less	$ 27,752	$ 30,700
Greater than one year and less than five years	5,705	6,134
Total available-for-sale securities	33,457	36,834
One year or less	27,727	30,701
Greater than one year and less than five years	5,699	6,140
Total available-for-sale securities	$ 33,426	$ 36,841

This item represents the cost of debt securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

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Fair value of available-for-sale debt securities maturing in the second fiscal year through the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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