Stock-Based Compensation and Directors Stock Purchase Plan (Summary Of The Status Of Nonvested Share Awards) (Details) |
12 Months Ended |
---|---|
Dec. 31, 2017
$ / shares
shares
| |
Nonvested Share Awards [Roll Forward] | |
Nonvested, share awards, beginning balance | shares | 1,461,713 |
Granted, Shares | shares | 263,123 |
Vested, Shares | shares | (442,435) |
Forfeited, Shares | shares | (27,883) |
Canceled, Shares | shares | 0 |
Nonvested, share awards, ending balance | shares | 1,254,518 |
Nonvested Weighted Average Grant Date Fair Value [Roll Forward] | |
Nonvested, Weighted Average Grant Date Fair Value, Beginning Balance | $ / shares | $ 33.02 |
Granted, Weighted Average Grant Date Fair Value | $ / shares | 54.56 |
Vested, Weighted Average Grant Date Fair Value | $ / shares | 29.41 |
Forfeited, Weighted Average Grant Date Fair Value | $ / shares | 39.12 |
Canceled, Weighted Average Grant Date Fair Value | $ / shares | 0.00 |
Nonvested , Weighted Average Grant Date Fair Value, Ending Balance | $ / shares | $ 38.67 |