| **Net Income Per Common Share**            | 3 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
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| **Net Income Per Common Share [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |
| Net Income Per Common Share                | Note 7             Net Income per Common Share 

 

Basic net income per common share is based on the weighted average number of common shares outstanding.  Diluted net income per common share is based on the weighted average number of common shares outstanding and potentially dilutive shares.  The dilutive effect of employee stock-based compensation is included in the computation of diluted net income per common share.  The dilutive effect of stock-based compensation is calculated using the treasury stock method and expected proceeds upon exercise or issuance of the stock-based compensation.  The following table summarizes the shares, in thousands, used in computing basic and diluted net income per common share: 

 

 

						 

						 

						 

						 

						 

 

						 

						 

						 

						 

						 

 

						 

						 

Three Months Ended

 

						 

						 

March 31,

 

						 

						 

2014

						 

2013

 

Average common shares outstanding during the period for basic computation

						 
176,839 				
						 
175,415 				
 

Dilutive effect of employee stock-based compensation

						 
971 				
						 
1,084 				
 

Average common shares outstanding during the period for diluted computation

						 
177,810 				
						 
176,499 				
 

						 

						 

						 

						 

						 

 

For the three months ended March 31, 2014, all of the Company’s employee stock options were included in the calculations of diluted net income per share as the calculated cost to exercise the stock options was less than the average market price of the Company’s common stock during these periods.  For the three months ended March 31, 2013, employee stock options to purchase 494,156 shares of common stock, were excluded from the calculations of diluted net income per share as the calculated cost to exercise the stock options was greater than the average market price of the Company’s common stock during these periods.  |

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| - Definition
The entire disclosure for earnings per share.
+ References
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