Commitments and Contingencies - Activity Related to Asbestos Claims (Detail) - Asbestos Related Matters [Member] - Claim Claim in Thousands		12 Months Ended
		Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Number of Pending Claims [Roll Forward]
Pending claims - Beginning		62	79	96
New claims		4	4	5
Settlements		(1)	(2)	(3)
Dismissals	[1]	(28)	(19)	(19)
Pending claims - Ending		37	62	79
Inactive [Member]
Number of Pending Claims [Roll Forward]
Pending claims - Beginning		13	13
Pending claims - Ending		0	13	13
Active [Member]
Number of Pending Claims [Roll Forward]
Pending claims - Beginning		49	66
Pending claims - Ending		37	49	66

[1] (a)Inactive claims represent pending claims in Mississippi filed in 2004 or prior, which have been excluded from our asbestos measurement because the plaintiffs cannot demonstrate a significant compensable loss. As of December 31, 2015, all inactive claims have been dismissed.