Summary of Revenues Disaggregated Based on Timing of Revenue Recognition (Detail) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Disaggregation of Revenue [Line Items]
Total revenues		$ 821,817	$ 754,235	$ 2,494,296	$ 2,423,259
U.S. Operating Segment
Disaggregation of Revenue [Line Items]
Total revenues	[1]	633,045	582,275	1,930,787	1,887,692
International Operating Segment
Disaggregation of Revenue [Line Items]
Total revenues		188,772	171,960	563,509	535,567
Goods and Services Transferred at a Point in Time
Disaggregation of Revenue [Line Items]
Total revenues		779,234	717,140	2,365,530	2,306,928
Goods and Services Transferred at a Point in Time | U.S. Operating Segment
Disaggregation of Revenue [Line Items]
Total revenues	[1]	610,063	561,849	1,860,828	1,824,138
Goods and Services Transferred at a Point in Time | International Operating Segment
Disaggregation of Revenue [Line Items]
Total revenues		169,171	155,291	504,702	482,790
Goods and Services Transferred Over Time
Disaggregation of Revenue [Line Items]
Total revenues		42,583	37,095	128,766	116,331
Goods and Services Transferred Over Time | U.S. Operating Segment
Disaggregation of Revenue [Line Items]
Total revenues	[1]	22,982	20,426	69,959	63,554
Goods and Services Transferred Over Time | International Operating Segment
Disaggregation of Revenue [Line Items]
Total revenues		$ 19,601	$ 16,669	$ 58,807	$ 52,777

[1] U.S. segment revenues include eliminations of intercompany transactions with the international operating segment.  See Note 16 for additional information on intercompany eliminations.