The Company and Summary of Significant Accounting Policies - Additional Information (Detail) shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2016 USD ($) Categories shares	Mar. 31, 2015 shares
Organization and Summary of Significant Accounting Policies Disclosure [Line Items]
Number of business channels | Categories	2
Number of revenue and cost categories | Categories	2
Unvested service-based restricted stock awards included in the calculation of earnings per share | shares	0.7	0.7
Deposits Assets
Organization and Summary of Significant Accounting Policies Disclosure [Line Items]
Cash subject to FDIC insurance | $	$ 10.5
Cash not subject to FDIC insurance | $	$ 95.3