| **Net Income Per Common Share (Tables)**      | 9 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
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| **Net Income Per Common Share [Abstract]**    |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |
| Reconciliation of net income per common share | The reconciliation of the net income per common share calculation is as follows:   For the three months ended  For the nine months ended ($ and shares in thousands, except per share amounts) September 30,  September 30,    2012  2011  2012  2011 Net income used for basic and diluted earnings            per common share:            Net income attributable to common shareholders of Frontier $67,000  $20,395  $111,757  $107,367                   Less: Dividends paid on unvested restricted stock awards  (717)  (914)  (2,189)  (2,835)Total basic and diluted net income attributable to common                shareholders of Frontier $66,283  $19,481  $109,568  $104,532                   Basic earnings per common share:                Total weighted average shares and unvested restricted stock awards                outstanding - basic  998,488   995,188   997,437   994,642 Less: Weighted average unvested restricted stock awards  (7,193)  (4,929)  (7,137)  (4,917)Total weighted average shares outstanding - basic  991,295   990,259   990,300   989,725                   Net income per share attributable to common shareholders of Frontier $0.07  $0.02  $0.11  $0.11                  Diluted earnings per common share:                Total weighted average shares outstanding - basic  991,295   990,259   990,300   989,725 Effect of dilutive shares  163   535   667   1,478 Effect of dilutive stock units  -   490   -   490 Total weighted average shares outstanding - diluted  991,458   991,284   990,967   991,693                   Net income per share attributable to common shareholders of Frontier $0.07  $0.02  $0.11  $0.11                    |

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| - Definition
Tabular disclosure of the effect of income (loss) on basic earnings per share.
+ References
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