Schedule II - Consolidated Valuation Accounts (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Allowance for Doubtful Accounts - Accounts Receivable [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance Beginning of Year	$ 7,270	$ 7,544	$ 8,415
Reserves Obtained in Acquisitions	0	0	774
Additions - Charged to Cost and Expenses	916	3,317	509
Deductions - Amounts Charged-Off	(1,448)	(3,591)	(2,154)
Balance End of Year	6,738	7,270	7,544
Allowance for Deferred Income Tax Asset Valuation [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Balance Beginning of Year	100,205	109,240	109,677
Reserves Obtained in Acquisitions	0	0	0
Additions - Charged to Cost and Expenses	2,385	0	1,162
Deductions - Amounts Charged-Off	0	(9,035)	(1,599)
Balance End of Year	$ 102,590	$ 100,205	$ 109,240