Incentive Plan (Tables)

3 Months Ended

Mar. 31, 2012

Incentive Plan [Abstract]

Summary Of Incentive Award Plan's Stock Option

	Period ended March 31, 2012
	Shares			Weighted average exercise price
Options outstanding, beginning of period		337,760		$	24.17
Exercised		(32,758	)		39.62
Cancelled / Forfeited		—			—
Options outstanding, end of period		305,002		$	22.51
Exercisable, end of period		293,751		$	21.78

Summary Of Stock Options Outstanding And Exercisable

Options outstanding									Options exercisable
Exercise price	Number outstanding		Weighted average remaining contractual life (years)		Weighted average exercise price		Aggregate intrinsic value		Number exercisable		Weighted average remaining contractual life (years)		Weighted average exercise price		Aggregate intrinsic value
$12.00-13.02		181,119		2.58	$	12.00	$	11,223,944		181,119		2.58	$	12.00	$	11,223,944
$20.37-28.09		17,000		3.64		21.28		895,760		17,000		3.64		21.28		895,760
$33.18-41.73		106,883		5.02		40.52		3,575,032		95,632		5.01		40.38		3,212,300
		305,002		3.49	$	22.51	$	15,694,736		293,751		3.43	$	21.78	$	15,332,004