Stockholders' Equity - Shareholder Rights Plan (Details)	Jun. 30, 2008 item $ / item
Shareholder Rights Plan
Purchase price of each Right, before the amendment and restatement of the Rights (in dollars per one one-thousandth of a share)	64.75
Purchase price of each Right, after the amendment and restatement of the Rights (in dollars per one one-thousandth of a share)	400.00
Number of shares of Series A Junior Participating Preferred Stock each Right entitles a holder to purchase | item	0.001
Minimum ownership percentage in the outstanding shares of voting stock from the commencement of a tender offer that would result in the exercise of shares under one condition of the Agreement (as a percent)	15.00%