Changes in Plan Assets and Benefit Obligation Recognized in Accumulated Other Comprehensive Income (Loss) (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Schedule Of Defined Contribution Plans Disclosures [Line Items]
Pension liability OCI, beginning of year	$ (1,495)
Establishment of plan		(1,768)
Net gain	(3,014)	139
Amortization of prior service cost	150	134
Total	$ (4,359)	$ (1,495)