Equity Incentive Plans (Narrative) (Details) (USD $)	12 Months Ended											12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009	Dec. 15, 2011	Mar. 31, 2011	Mar. 23, 2011	Mar. 15, 2011	Feb. 21, 2011	Feb. 21, 2010	Feb. 21, 2008	Sep. 30, 2003	Dec. 31, 2011 Restricted Stock Units (RSUs) [Member]	Dec. 31, 2010 Restricted Stock Units (RSUs) [Member]	Dec. 31, 2009 Restricted Stock Units (RSUs) [Member]	Dec. 15, 2011 Restricted Stock Units (RSUs) [Member]	Feb. 21, 2011 Restricted Stock Units (RSUs) [Member]	Feb. 21, 2010 Restricted Stock Units (RSUs) [Member]	May 31, 2005 2005 Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum term of options granted, years	10
Annual vesting increments, percentage	20.00%
Option compensation expense	$ 1,000,000	$ 3,000,000	$ 5,400,000									$ 758,000	$ 327,000	$ 327,000
Unrecognized stock-based compensation expense related to stock options	904,000											2,100,000
Unrecognized stock-based compensation expense related to stock options expected to be recognized period, years	1.2											1.6
Stock options exercised, Shares	86,860		1,280
Cash received totaled	1,300,000		13,000
Aggregate intrinsic value for options exercised	172,000		8,000
Fair value of stock options vested	$ 2,600,000	$ 4,900,000
Shares available for future grant under incentive plan	2,202,587										7,000,000							3,131,854
Restricted stock units granted to eligible employees					65,243	50,174	15,069			82,291					77,404
Common stock shares issued upon vesting restricted stock units	82,860,122	82,739,348														12,633	15,006
Restricted stock units granted maximum term, years	5
Annual vesting increments of restricted stock grants	20.00%
Common stock, market price				$ 13.69		$ 16.15	$ 16.14	$ 18.79	$ 9.64