Changes in Accumulated Balances of Other Comprehensive Income (Loss) (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	$ 360
Other comprehensive income (loss) before reclassifications	291
Amounts reclassified from accumulated other comprehensive income (loss)	(732)
Net current period other comprehensive income (loss)	(441)	1,261	(1,218)
Ending balance	(81)	360
Unrealized gains (losses) on available-for-sale marketable securities
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	224
Other comprehensive income (loss) before reclassifications	65
Amounts reclassified from accumulated other comprehensive income (loss)	(379)
Net current period other comprehensive income (loss)	(314)
Ending balance	(90)
Unrealized gains (losses) on cash flow hedges
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	216
Other comprehensive income (loss) before reclassifications	283
Amounts reclassified from accumulated other comprehensive income (loss)	(515)
Net current period other comprehensive income (loss)	(232)
Ending balance	(16)
Estimated tax (expense) benefit
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	(80)
Other comprehensive income (loss) before reclassifications	(57)
Amounts reclassified from accumulated other comprehensive income (loss)	162
Net current period other comprehensive income (loss)	105
Ending balance	$ 25