Stock-Based Compensation (Tables)

	2013		2012		2011
Units granted	129,620		202,278		292,242
Grant date fair value (a)	$	55.21	$	49.31	$	41.98

(a) Weighted-average grant date fair value.

Nonvested shares	Shares	Weighted-Average Grant Date Fair Value
Nonvested at January 1, 2013	480,753	$	43.58
Granted	129,620	55.21
Vested	191,988	40.33
Forfeited	20,409	45.70
Nonvested at December 31, 2013	397,976	47.74

The amount of cash required to settle the payments on restricted stock units is (dollars in millions):

Year	2013		2012		2011
2007 Grant	$	—	$	—	$	1.0
2008 Grant	—		1.9		1.6
2009 Grant	3.0		1.7		1.5
2010 Grant	2.3		0.6		0.6
2011 Grant	2.5		0.7		—
2012 Grant	2.2		—		—

	2013		2012		2011
Units granted (a)	176,332		185,878		175,072
Grant date fair value (b)	$	55.45	$	47.40	$	41.71

(a) Reflects the target payout level.

(b) Weighted-average grant date fair value.

Nonvested shares (a)	Shares	Weighted-Average Grant Date Fair Value
Nonvested at January 1, 2013	347,690	$	44.67
Granted	176,332	55.45
Increase in performance factor	40,183	41.71
Vested	200,915	41.71
Forfeited	18,894	48.11
Nonvested at December 31, 2013	344,396	51.13

(a) Nonvested shares are reflected at target payout level. The increase or decrease in the number of shares from the target level to the estimated actual payout level is included in the increase for performance factor amounts in the year the award vests.

Options	Shares	Weighted- Average Exercise Price
Outstanding at January 1, 2013	7,925	$	32.29
Exercised	3,625	32.29
Forfeited or expired	4,300	32.29
Outstanding at December 31, 2013	—	—