Description of Business and Accounting Policies - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Summary Of Business And Accounting Policies [Line Items]
Entity incorporation date	1994-07
Common stock equivalent shares excluded from computations of basic and diluted income per share	901,069	990,831
Letter of credit expiration year	2020
Advertising expense	$ 558,000	$ 501,000
Office furniture and equipment [Member]
Summary Of Business And Accounting Policies [Line Items]
Leasehold improvements estimated useful life	3 years
Minimum [Member]
Summary Of Business And Accounting Policies [Line Items]
Intangible assets useful life range	1 year
Minimum [Member] | Leasehold improvements [Member]
Summary Of Business And Accounting Policies [Line Items]
Leasehold improvements estimated useful life	2 years
Maximum [Member]
Summary Of Business And Accounting Policies [Line Items]
Intangible assets useful life range	10 years
Maximum [Member] | Leasehold improvements [Member]
Summary Of Business And Accounting Policies [Line Items]
Leasehold improvements estimated useful life	10 years