Quantitative Information About Recurring Level 3 Fair Value Measurements (Detail) (Fair Value Inut Level 3, USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended
	Mar. 31, 2015	Dec. 31, 2014
Fair Value Inut Level 3
Quantitative Information About Recurring Fair Value Measurements [Line Items]
Fair Value	$ 2,816	$ 2,801
Valuation Technique	Discounted cash flow	Discounted cash flow
Significant Unobservable Inputs	Probability of default	Probability of default
Range of Inputs, Minimum	0.82%	0.79%
Range of Inputs, Maximum	2.52%	2.49%