Stock-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2011

Stock-Based Compensation

Summary of granted restricted stock units and stock grants and the weighted average fair value

	2011		2010		2009
Units granted	292,242		202,341		261,006
Grant date fair value (a)	$	41.98	$	37.47	$	30.25

(a) weighted average fair value

Summary of the status of restricted stock units and stock grants and changes during the year

Nonvested shares	Shares	Weighted-Average Grant-Date Fair Value
Nonvested at January 1, 2011	223,681	$	35.69
Granted	293,242	41.98
Vested	98,362	37.84
Forfeited	2,330	37.93
Nonvested at December 31, 2011	416,231	39.61

Schedule of amount of cash required to settle the payments on restricted stock units

Year	2011		2010		2009
2007 Grant	$	1.0	$	0.9	$	0.8
2008 Grant	1.6		1.5		1.3
2009 Grant	1.5		1.4		—
2010 Grant	0.6		—		—

Summary of the performance shares granted and the weighted average fair value

	2011		2010		2009
Units granted	175,072		178,722		240,624
Grant date fair value (a)	$	41.71	$	37.57	$	30.19

(a)weighted average grant date fair value

Summary of the status of performance shares and changes during the year

Nonvested shares	Shares	Weighted-Average Grant-Date Fair Value
Nonvested at January 1, 2011	395,312	$	33.44
Granted	175,072	41.71
Vested	218,310	30.14
Forfeited	4,128	36.09
Nonvested at December 31, 2011	347,946	39.64

Summary of stock option activity under prior equity incentive plans

Options	Shares	Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Term (Months)	Aggregate Intrinsic Value (dollars in thousands)
Outstanding atJanuary 1, 2011	82,224	$	39.37
Exercised	44,766	40.70
Forfeited or expired	14,500	42.55
Outstanding atDecember 31, 2011	22,958	34.75		11	$	308
Exercisable atDecember 31, 2011	22,958	34.75		11	$	308