Quarterly report pursuant to Section 13 or 15(d)

Selected Balance Sheet Data - Additional Information (Detail)

v3.7.0.1
Selected Balance Sheet Data - Additional Information (Detail)
 3 Months Ended
Jan. 01, 2017
Jan. 01, 2016
Jan. 01, 2014
Mar. 31, 2017
USD ($)
Installments
Mar. 31, 2016
USD ($)
Dec. 31, 2016
USD ($)
Mar. 31, 2013
USD ($)
Schedule Of Accrued Expenses [Line Items]              
SARs frozen liability amount       $ 19,447,000   $ 20,949,000  
Interest expense       $ 382,000 $ 391,000    
Maximum payment deferral period for certain commissions payable       3 years      
SARs [Member]              
Schedule Of Accrued Expenses [Line Items]              
SARs frozen liability amount             $ 20,000,000
SARs liability frozen value date       Mar. 31, 2013      
SARs liability interest accrual commencement date       Jan. 01, 2014      
Interest expense       $ 233,000 $ 229,000    
Treasury note term     10 years        
Base spread on SARs liability variable rate     2.00%        
SARs liability interest accrual rates 4.446% 4.273%          
SARs liability number of annual installments | Installments       10      
Estimated payouts description       Estimated payouts within the next twelve months for participants that have separated from service have been classified as current.      
Payments made during the period       $ 1,400,000      
Deferred Compensation Liability [Member]              
Schedule Of Accrued Expenses [Line Items]              
Estimated payouts description       Estimated payouts within the next twelve months for participants that have separated from service have been classified as current.      
Payments made during the period       $ 37,000      
Deferred Compensation Liability, Minimum Payout Period       2 years      
Deferred Compensation Liability, Maximum Payout Period       15 years      
Fair value of deferred compensation plan assets       110.00%