Reconciliation of Adjusted Segment Earnings before Interest, Taxes, Depreciation and Amortization (Detail) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Segment Reporting [Abstract]
Total Adjusted Segment EBITDA									$ 283,435	$ 291,375	$ 313,260
Segment depreciation expense									(27,717)	(30,267)	(28,203)
Amortization of intangible assets									(11,726)	(15,521)	(22,954)
Special charges										(16,339)	(38,414)
Goodwill impairment charge											(83,752)
Unallocated corporate expenses, excluding special charges									(81,348)	(84,545)	(72,053)
Interest income and other	$ 392	$ 2,027	$ 950	$ (137)	$ 1,205	$ 1,014	$ 1,448	$ 1,003	3,232	4,670	1,748
Interest expense	(6,231)	(11,696)	(12,473)	(12,368)	(12,488)	(12,634)	(12,908)	(12,655)	(42,768)	(50,685)	(51,376)
Loss on early extinguishment of debt		(19,589)							(19,589)
Remeasurement of acquisition-related contingent consideration									1,867	2,723	13,555
Income before income tax provision	$ 17,926	$ 16,486	$ 35,631	$ 35,343	$ 10,623	$ 34,851	$ 27,472	$ 28,465	$ 105,386	$ 101,411	$ 31,811