Schedule II - Valuation and Qualifying Accounts and Reserves (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Allowance for doubtful accounts [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Year	$ 4,415		$ 4,753		$ 4,158
Charged to Expenses / Against Revenue	1,814	[1]	2,468	[1]	1,065	[1]
Deductions - Write-offs	(161)	[2]	(2,284)	[2]	(470)	[2]
Adjustment	(73)	[3]	(522)	[3]	0	[3]
Balance at End of Year	5,995		4,415		4,753
Valuation allowance for income taxes [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Year	741		595		1,615
Charged to Expenses / Against Revenue	48	[1]	673	[1]	73	[1]
Deductions - Write-offs	0	[2]	(527)	[2]	(1,093)	[2]
Adjustment	0	[3]	0	[3]	0	[3]
Balance at End of Year	$ 789		$ 741		$ 595

[1] Primarily additional reserves for bad debts

[2] Primarily accounts receivable balances written off, net of recoveries, and the expiration of loss carryforwards

[3] Related to discontinued operations