13. Stock Incentive Plans and Stock Purchase Plan:

The Company's 2008 Incentive Compensation Plan (the "2008 Incentive Plan") provides for grants of stock options, stock appreciation rights, restricted stock, deferred stock, and other stock-related awards and performance awards that may be settled in cash, stock or other property. As provided in the 2008 Incentive Plan, no additional grants can be made from the Company's prior incentive plans, except that new awards will be permitted under the 2004 Incentive Compensation Plan (the "2004 Incentive Plan") to the extent that shares previously granted under the 2004 Incentive Plan are forfeited, expire or terminate. To date, the only equity awards made by the Company under the 2008 Incentive Plan are for stock options, restricted stock and deferred stock. Collectively, the Company's prior incentive plans and the 2008 Incentive Plan are referred to as the Stock Incentive Plans.

Under the 2008 Incentive Plan, options to purchase shares of common stock may be granted at a price not less than the fair market value of the shares on the date of grant. The options must be exercised within 10 years from the date of grant and generally become exercisable on a pro rata basis over a three-year period from the date of grant. The Company issues new shares of its common stock upon exercise of its stock options. Restricted stock awards generally vest over periods of three years upon the fulfillment of specified service-based conditions and in certain instances performance-based conditions. Deferred stock awards vest on a cliff basis over a term of five years upon the fulfillment of specified service-based and performance-based conditions or upon the satisfaction of specified performance-based conditions through December 31, 2018. The Company recognizes compensation expense related to its restricted stock and deferred stock awards ratably over the corresponding vesting periods. At December 31, 2011, the Company had approximately 1.3 million shares available for future grants and awards under its Stock Incentive Plans.

Under the Company's 1996 Non-Qualified Employee Stock Purchase Plan, as amended (the "Non-Qualified Plan"), employees are permitted to purchase the Company's common stock at 85% of market value on January 1st, April 1st, July 1st and October 1st of each year. In accordance with the provisions of accounting guidance for stock-based compensation, the Company recognizes stock-based compensation expense for the 15% discount received by participating employees. During the year ended December 31, 2011, 118,828 shares were issued under the Non-Qualified Plan. At December 31, 2011, the Company had approximately 555,000 shares reserved for issuance under the Non-Qualified Plan.

The Company recognized approximately $27.1 million, $25.7 million and $24.3 million of stock-based compensation expense related to its Stock Incentive Plans and Stock Purchase Plan during the years ended December 31, 2011, 2010 and 2009, respectively.

The activity related to the Company's restricted and deferred stock awards and the corresponding weighted average grant-date fair values for the year ended December 31, 2011 are as follows:


	Number of Shares			Weighted Average Fair Value
Non-vested shares at January 1, 2011		955,449		$	50.08
Awarded		427,152		$	70.99
Forfeited		(15,279	)	$	54.58
Vested		(388,969	)	$	48.84

Non-vested shares at December 31, 2011		978,353		$	59.64

The aggregate fair value of the restricted shares that vested during the years ended December 31, 2011, 2010 and 2009 was approximately $19.0 million, $14.4 million and $9.7 million, respectively.

The weighted average grant-date fair value of restricted and deferred stock awards that were granted during the years ended December 31, 2011, 2010 and 2009 was $70.99, $54.90 and $41.74, respectively.

At December 31, 2011, the total stock-based compensation cost related to non-vested restricted and deferred stock remaining to be recognized as compensation expense over a weighted-average period of approximately 1.5 years was $28.1 million.

The Company uses the Black-Scholes Model to estimate the fair value of each stock option on the date of grant. The weighted average grant-date fair values for stock options granted during the years ended December 31, 2011, 2010 and 2009 were $23.27, $18.89 and $12.19, respectively, which were calculated using the following weighted average assumptions for expected volatility, expected life, risk-free interest rate and dividend yield:


	Years Ended December 31,
	2011	2010	2009
Expected volatility	35%	35%	32% to 37%
Expected life—officers (in years)	4.5	4.5	4.5
Expected life—other employees (in years)	3.5	3.5	3.5
Risk-free interest rate	1.9%	2.1% to 2.3%	1.4% to 2.1%
Dividend yield	0%	0%	0%

Expected volatility is estimated using sequential periods of historical price data related to the Company's common stock. The Company assigns expected lives and corresponding risk-free interest rates to two separate homogenous employee groups consisting of officers and all other employees. The Company evaluates the estimated expected lives assigned to its two employee groups, officers and other employees, using historical exercise data, taking into consideration the impact of partial life cycle data, contractual term and post-vesting cancellations. The risk-free interest rates used are based on the published U.S. Treasury yield curve in effect at the time of the grant for instruments with a similar life. The dividend yield reflects the Company's dividend yield at the date of grant.

The activity and certain other information related to the Company's stock option awards for the year ended December 31, 2011 are as follows:


	Number of Shares			Weighted Average Exercise Price		Weighted Average Remaining Contractual Term (in years)		Aggregate Intrinsic Value (in millions)
Outstanding at January 1, 2011		2,567,933		$	44.50
Granted		41,400		$	72.50
Canceled		(3,833	)	$	37.59
Exercised		(551,927	)	$	44.42			$	14.1

Outstanding at December 31, 2011		2,053,573		$	45.10		4.8	$	55.3

Exercisable at December 31, 2011		1,910,919		$	44.33		4.5	$	52.9

The aggregate intrinsic value of stock options exercised during the years ended December 31, 2011, 2010 and 2009 was $14.1 million, $9.1 million and $21.8 million, respectively.

At December 31, 2011, the total stock-based compensation cost related to non-vested stock options remaining to be recognized as compensation expense over a weighted-average period of approximately 1.3 years was $0.9 million.

The excess tax benefit related primarily to restricted stock and stock options for the years ended December 31, 2011, 2010 and 2008 was approximately $7.1 million, $3.0 million and $6.9 million, respectively. The cash proceeds received from the exercise of stock options for the years ended December 31, 2011, 2010 and 2009 were approximately $24.5 million, $16.4 million and $12.5 million, respectively.