XML 26 R77.htm IDEA: XBRL DOCUMENT v3.2.0.727
(Textual) (Details)
$ / shares in Units, $ in Millions
3 Months Ended 6 Months Ended
Jun. 30, 2015
USD ($)
$ / shares
shares
Jun. 30, 2014
USD ($)
Jun. 30, 2015
USD ($)
$ / shares
shares
Jun. 30, 2014
USD ($)
Apr. 20, 2015
shares
Share-Based Compensation Plans (Textual) [Abstract]          
Share-based compensation expense | $ $ 0.8 $ 0.6 $ 1.5 $ 1.2  
Common stock available for future grants under share-based compensation plans         1,300,000
Restricted Stock Units (RSUs) [Member]          
Share-Based Compensation Plans (Textual) [Abstract]          
Corporation granted options to purchase restricted stock performance units     79,202    
Unrecognized compensation expense | $ $ 3.7   $ 3.7    
Unrecognized compensation expense, period for recognition     2 years 9 months 18 days    
Restricted Stock Units (RSUs) [Member] | Maximum [Member]          
Share-Based Compensation Plans (Textual) [Abstract]          
Restricted stock performance units eligible to vest as a multiple of number of units granted     1.5    
Restricted Stock Units (RSUs) [Member] | Minimum [Member]          
Share-Based Compensation Plans (Textual) [Abstract]          
Restricted stock performance units eligible to vest as a multiple of number of units granted     0.25    
Equity Option [Member]          
Share-Based Compensation Plans (Textual) [Abstract]          
Common stock available for future grants under share-based compensation plans 1,295,145   1,295,145    
Weighted-average remaining contractual terms for outstanding stock options     6 years 7 months 6 days    
Weighted-average remaining contractual terms for exercisable stock options     4 years 9 months 18 days    
Outstanding in-the-money stock options, intrinsic value | $ $ 6.9   $ 6.9    
Exercisable in-the-money stock options, intrinsic value | $ $ 4.7   $ 4.7    
Closing price of common stock | $ / shares $ 33.06   $ 33.06    
Unrecognized compensation expense | $ $ 4.0   $ 4.0    
Unrecognized compensation expense, period for recognition     3 years 10 months 24 days    
Vested & Nonvested [Member] | Employee Stock Option [Member]          
Share-Based Compensation Plans (Textual) [Abstract]          
Corporation granted options to purchase common stock     244,165    
Converted, Number of Options from Lake Michigan Acquisition     132,883