Employee Stock and Benefit Plans (Plan Information) (Details) (USD $) In Millions, except Share data, unless otherwise specified			0 Months Ended		12 Months Ended
	Dec. 31, 2013 2012 Equity Incentive Plan		Sep. 26, 2012 2012 Equity Incentive Plan Maximum	Sep. 26, 2012 2012 Equity Incentive Plan Stock Options	Dec. 31, 2013 2000 Equity Incentive Plan Stock Options	Dec. 31, 2012 2000 Equity Incentive Plan Stock Options	Dec. 31, 2011 2000 Equity Incentive Plan Stock Options	Dec. 31, 2013 2000 Equity Incentive Plan Stock Options Minimum	Sep. 26, 2012 Increase of Number of Shares Option 2012 Equity Incentive Plan	Sep. 26, 2012 Increase of Percentage of Shares Outstanding Option 2012 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity incentive plan annual increase (in shares)									3,050,000
Equity incentive plan, annual increase, percent of shares outstanding										5.00%
Award vesting period				4 years	4 years
Term of award				10 years	10 years
Expiration period			10 years
Number of shares available for grant	1,173,450	[1]
Award strike price as a percentage of market value								85.00%
Number of shares available for issuance					0
Number of shares subject to repurchase (in shares)					11,145	47,220
Number of unvested shares repurchased (in shares)					500	60,126	1,000
Liability for options early exercised					$ 0.1	$ 0.3

[1] See Note 8 for a description of these plans.