Share-Based Compensation (Narrative) (Details) (USD $) Share data in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Share-Based Compensation
Shares available and reserved for grant	1.1		1.1
Received cash from the exercise of stock options		$ 200,000	$ 700,000	$ 400,000
Compensation expense related to fair value of stock options	61,500	36,000	131,000	74,000
Entity vesting description			The Compensation Committee of the Company's Board of Directors administers the Plans and determines the exercise period, vesting period and all other terms of instruments issued under the Plans. Approximately 1.1 million shares were available and reserved for grant as of June 30, 2011.
Compensation expense related to granted nonvested shares	$ 1,600,000	$ 1,600,000	$ 3,100,000	$ 3,200,000

Received cash from the exercise of stock options

$ 200,000

$ 700,000

$ 400,000

The Compensation Committee of the Company's Board of Directors administers the Plans and determines the exercise period, vesting period and all other terms of instruments issued under the Plans. Approximately 1.1 million shares were available and reserved for grant as of June 30, 2011.