Annual report pursuant to Section 13 and 15(d)

Shareholders' Equity, Stock Options and Net Income per Share - Employee Activity Non-vested Shares (Details)

v3.3.1.900
Shareholders' Equity, Stock Options and Net Income per Share - Employee Activity Non-vested Shares (Details) - USD ($)
$ / shares in Units, shares in Thousands, $ in Thousands
12 Months Ended
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Share-based compensation $ 7,486 $ 6,681 $ 6,178
Employee Non-vested Shares [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Share-based awards, vesting period 3 years    
Outstanding at beginning of year (shares) 190 186 168
Granted (shares) 100 99 98
Vested (shares) (93) (94) (68)
Forfeited (shares) (6) (1) (12)
Outstanding at end of year (shares) 191 190 186
Weighted average grant date fair value of non-vested shares at beginning of year $ 40 $ 35 $ 33
Weighted Average Grant Date Fair Value 51 42 37
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value 39 43 37
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period, Weighted Average Grant Date Fair Value 45 37 36
Weighted average grant date fair value non-vested shares at end of year $ 46 $ 40 $ 35
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Granted in Period, Total Fair Value $ 8,773 $ 7,585 $ 6,588
Grant date fair value of shares that vested during the year 4,694 4,008 2,503
Share-based compensation 4,070 3,626 3,058
Tax benefit related to share-based compensation expense 1,591 $ 1,385 $ 1,165
Unrecognized compensation cost $ 5,085