Accumulated Other Comprehensive Income (Loss) - Summary of Reclassifications Out of Accumulated Other Comprehensive Income (Loss) (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Equity [Abstract]
Current period unrealized gain (loss) on cash flow hedges, Pre-Tax Amount	$ (1,655)	$ 712	$ 1,079
Reclassification adjustments on cash flow hedges, Pre-Tax Amount	653	(1,829)	598
Unrealized gains (losses) on cash flow hedges, net, Pre-Tax Amount	(1,002)	(1,117)	1,677
Current period unrealized gain (loss) on investments, Pre-Tax Amount	(59)	34	291
Reclassification adjustments on investments, Pre-Tax Amount	0	(206)	(57)
Unrealized gains (losses) on investments, net, Pre-Tax Amount	(59)	(172)	234
Other comprehensive income (loss), Pre-Tax Amount	(1,061)	(1,289)	1,911
Current period unrealized gain (loss) on cash flow hedges, Tax Expense (Benefit)	0	0	427
Reclassification adjustments on cash flow hedges, Tax Expense (Benefit)	0	0	0
Unrealized gains (losses) on cash flow hedges, net, Tax Expense (Benefit)	0	0	427
Current period unrealized gain (loss) on investments, Tax Expense (Benefit)	0	0	7
Reclassification adjustments on investments, Tax Expense (Benefit)	0	0	0
Unrealized gains (losses) on investments, net, Tax Expense (Benefit)	0	0	7
Other comprehensive income (loss), Tax Expense (Benefit)	0	0	434
Current period unrealized gain (loss) on cash flow hedges, After-Tax Amount	(1,655)	712	652
Reclassification adjustments on cash flow hedges, After-Tax Amount	653	(1,829)	598
Unrealized gains (losses) on cash flow hedges, net, After-Tax Amount	(1,002)	(1,117)	1,250
Current period unrealized gain (loss) on investments, After-Tax Amount	(59)	34	284
Reclassification adjustments on investments, After-Tax Amount	0	(206)	(57)
Unrealized gains (losses) on investments, After-Tax Amount	(59)	(172)	227
Other comprehensive income (loss)	$ (1,061)	$ (1,289)	$ 1,477