v3.3.1.900
Consolidated Statements of Shareholders' Equity - USD ($)
shares in Thousands, $ in Thousands
Total
Non-Voting Common Stock [Member]
Voting Common Stock [Member]
Additional Paid-in Capital [Member]
AOCI Attributable to Parent [Member]
Retained Earnings [Member]
Balance at Dec. 31, 2012 $ 499,615 $ 1,246 $ 285 $ 295,582 $ (51) $ 202,553
Balance, Shares at Dec. 31, 2012   12,565 2,853      
Net earnings 58,956         58,956
Unrealized gain (loss) on short-term investments 28       28  
Changes in pension plan assets and benefit obligations (1)       (1)  
Amortization of unearned stock-based compensation 2,403     2,403    
Issuance of non-voting common stock (upon vesting of restricted stock units) 17 $ 17        
Issuance of non-voting common stock (upon vesting of restricted stock units), shares   4        
Cancellation of restricted non-voting stock units for tax withholdings on vested shares (65) $ (6)   (59)    
Cancellation of restricted non-voting stock units for tax withholdings on vested shares, shares   (1)        
Issuance of voting common stock (upon vesting of restricted stock units) 9   $ 9      
Issuance of voting common stock (upon vesting of restricted stock units), shares     84      
Cancellation of restricted voting stock units for tax withholdings on vested shares (997)   $ (3) (994)    
Cancellation of restricted voting stock units for tax withholdings on vested shares, shares     (31)      
Balance at Dec. 31, 2013 559,965 $ 1,257 $ 291 296,932 (24) 261,509
Balance, Shares at Dec. 31, 2013   12,568 2,906      
Net earnings 32,688         32,688
Unrealized gain (loss) on short-term investments (173)       (173)  
Changes in pension plan assets and benefit obligations 10       10  
Amortization of unearned stock-based compensation 4,753     4,753    
Issuance of non-voting common stock (upon vesting of restricted stock units) 1 $ 1        
Issuance of non-voting common stock (upon vesting of restricted stock units), shares   12        
Cancellation of restricted non-voting stock units for tax withholdings on vested shares (178)     (178)    
Cancellation of restricted non-voting stock units for tax withholdings on vested shares, shares   (4)        
Other 2     26 (24)  
Balance at Dec. 31, 2014 597,068 $ 1,258 $ 291 301,533 (211) 294,197
Balance, Shares at Dec. 31, 2014   12,576 2,906      
Net earnings 26,924         26,924
Unrealized gain (loss) on short-term investments (384)       (384)  
Changes in pension plan assets and benefit obligations 4       4  
Amortization of unearned stock-based compensation 5,799     5,799    
Issuance of non-voting common stock (upon vesting of restricted stock units) 18 $ 18        
Issuance of non-voting common stock (upon vesting of restricted stock units), shares   179        
Cancellation of restricted non-voting stock units for tax withholdings on vested shares (2,203) $ (7)   (2,196)    
Cancellation of restricted non-voting stock units for tax withholdings on vested shares, shares   (70)        
Purchase and retirement of treasury stock (252)     (252)    
Other 24       24  
Balance at Dec. 31, 2015 $ 626,998 $ 1,269 $ 291 $ 304,884 $ (567) $ 321,121
Balance, Shares at Dec. 31, 2015   12,685 2,906