The Company and Summary of Significant Accounting Policies - Additional Information (Detail) $ in Thousands, shares in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017 USD ($) Categories	Jun. 30, 2016 USD ($)	Jun. 30, 2017 USD ($) Categories shares	Jun. 30, 2016 USD ($) shares
Organization and Summary of Significant Accounting Policies Disclosure [Line Items]
Number of business channels | Categories	2		2
Number of revenue and cost categories | Categories	2		2
Increased in cash provided by operating activities			$ 24,433	$ 34,557
Increased in cash used in financing activities			(11,976)	(959)
Reduction in provision for income taxes due to excess tax benefits	$ 601	$ 495	$ 1,096	$ 1,089
Unvested service-based restricted stock awards included in the calculation of earnings per share | shares			0.6	0.6
Total minimum lease commitments	17,900		$ 17,900
Accounting Standards Update 2016-09
Organization and Summary of Significant Accounting Policies Disclosure [Line Items]
Increased in cash provided by operating activities				$ 2,500
Increased in cash used in financing activities				$ 2,500
Reduction in provision for income taxes due to excess tax benefits	100		500
Accounting Standards Update 2016-09 | Retained Earnings
Organization and Summary of Significant Accounting Policies Disclosure [Line Items]
Adoption of ASU 2016-09	(400)		(400)
Accounting Standards Update 2016-09 | Additional Paid-in Capital
Organization and Summary of Significant Accounting Policies Disclosure [Line Items]
Adoption of ASU 2016-09	400		400
Deposits Assets
Organization and Summary of Significant Accounting Policies Disclosure [Line Items]
Cash subject to FDIC insurance	8,200		8,200
Cash not subject to FDIC insurance	$ 127,200		$ 127,200