Share-Based Compensation

6 Months Ended

Jun. 30, 2011

Share-Based Compensation

12.        Share-Based Compensation

Our stock compensation plans permit the grant of incentive and nonqualified stock options, common stock, deferred common stock units, restricted stock and restricted stock units to our employees and directors.  Generally, stock options granted under our stock compensation plans vest over a three-year period, with one-third vesting in each year. Common stock and deferred common stock units granted under our stock compensation plans are vested immediately, and we recognize compensation expense related to those grants on the grant date.  Restricted stock and restricted stock units granted under our stock compensation plans vest over a three-year period, with one-third vesting in each year. We recognize compensation expense related to our stock compensation plans in the General and administrative expenses caption on our Condensed Consolidated Statements of Income. The following table summarizes the share-based compensation expense for the periods presented:

	Three Months Ended June 30,				Six Months Ended June 30,
	2011		2010		2011		2010
Stock option plans	$	1,379	$	1,276	$	2,787	$	3,385
Common, deferred and restricted stock and restricted stock unit plans		634		392		1,022		1,304
	$	2,013	$	1,668	$	3,809	$	4,689