Recently Issued Accounting Pronouncements - Summary of Impact of Adoption of Accounting Standards on Condensed Consolidated Balance Sheet (Detail) - USD ($)
$ in Thousands
Mar. 31, 2018
Jan. 01, 2018
Dec. 31, 2017
Assets:      
Accounts receivable, net $ 34,064   $ 34,461
Prepaid expenses and other current assets 6,455   5,714
Other assets 4,750   3,112
Liabilities:      
Accrued expenses and other current liabilities 38,127   43,096
Deferred revenue     15,102
Deferred revenue 15,889   15,102
Other long-term liabilities 5,830   6,428
Deferred income taxes 27,135   28,004
Stockholders' equity:      
Retained earnings 100,673   $ 97,815
Accounting Standards Update 2014-09 [Member]      
Assets:      
Accounts receivable, net   $ 41,513  
Prepaid expenses and other current assets   6,141  
Other assets   3,762  
Liabilities:      
Deferred revenue   12,179  
Other long-term liabilities   5,603  
Deferred income taxes   30,931  
Stockholders' equity:      
Retained earnings   106,765  
Accounting Standards Update 2014-09 [Member] | Difference between Revenue Guidance in Effect before and after Topic 606 [Member]      
Assets:      
Accounts receivable, net 5,729 7,052  
Prepaid expenses and other current assets 108 427  
Other assets 1,080 650  
Liabilities:      
Accrued expenses and other current liabilities 2,161    
Deferred revenue   (2,923)  
Deferred revenue (1,660)    
Other long-term liabilities (468) (825)  
Deferred income taxes 184 2,927  
Stockholders' equity:      
Retained earnings 6,700 $ 8,950  
Accounting Standards Update 2014-09 [Member] | Calculated under Revenue Guidance in Effect before Topic 606 [Member]      
Assets:      
Accounts receivable, net 28,335    
Prepaid expenses and other current assets 6,347    
Other assets 3,670    
Liabilities:      
Accrued expenses and other current liabilities 35,966    
Deferred revenue 17,549    
Other long-term liabilities 6,298    
Deferred income taxes 26,951    
Stockholders' equity:      
Retained earnings $ 93,973