Amounts Recognized in AOCI (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning balance, net of income tax	$ 4,249,647
Other comprehensive income (loss), Pretax amount	2,360	$ 5,083	$ 631
Other comprehensive income (loss), Income tax effect	(4,648)	(2,980)	(1,053)
Total other comprehensive income (loss), net of tax	(2,288)	2,103	(422)
Ending balance, net of income tax	4,533,220	4,249,647
Net Unrealized Gains (Losses) on Effective Cash Flow Hedges
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning balance, net of income tax	(776)	(3,247)
Other comprehensive income (loss), Pretax amount	1,271	4,634
Other comprehensive income (loss), Income tax effect	(476)	(2,163)
Total other comprehensive income (loss), net of tax	795	2,471
Ending balance, net of income tax	19	(776)	(3,247)
Foreign Currency Translation Adjustment
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning balance, net of income tax	(4,159)	(2,431)
Other comprehensive income (loss), Pretax amount	(10,038)	(1,728)
Total other comprehensive income (loss), net of tax	(10,038)	(1,728)
Ending balance, net of income tax	(14,197)	(4,159)	(2,431)
Unrealized Loss on Marketable Security
Accumulated Other Comprehensive Income Loss [Line Items]
Other comprehensive income (loss), Pretax amount	(2,229)
Other comprehensive income (loss), Income tax effect	831
Total other comprehensive income (loss), net of tax	(1,398)
Ending balance, net of income tax	(1,398)
Minimum Pension Liability
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning balance, net of income tax	(18,194)	(19,554)
Other comprehensive income (loss), Pretax amount	13,356	2,177
Other comprehensive income (loss), Income tax effect	(5,003)	(817)
Total other comprehensive income (loss), net of tax	8,353	1,360
Ending balance, net of income tax	(9,841)	(18,194)	(19,554)
Accumulated Other Comprehensive Income (Loss)
Accumulated Other Comprehensive Income Loss [Line Items]
Beginning balance, net of income tax	(23,129)	(25,232)
Ending balance, net of income tax	$ (25,417)	$ (23,129)	$ (25,232)