Stock-Based and Other Compensation Plans	3 Months Ended
Mar. 31, 2013
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Disclosure of Compensation Related Costs, Share-based Payments and Other Compensation [Text Block]	Stock-Based and Other Compensation Plans The Company grants stock options, stock appreciation rights (“SARs”), performance-based awards, and time-based restricted shares, some of which are cash-settled awards with the final payment indexed to the percentage change in the Company’s stock price from the date of grant. For the three months ended March 31, 2013, the Company recognized a stock-based compensation benefit of $1.7 million, inclusive of a $3.9 million mark-to-market gain on awards indexed to the Company's stock price. For the three months ended March 31, 2012, the Company recognized stock-based compensation expense of $3.5 million, which reflected $1.5 million of mark-to-market expense. As of March 31, 2013, there was $6.9 million of unrecognized compensation expense related to these awards. The remaining compensation expense for the stock options, SARs and restricted awards is expected to be recognized over a weighted-average period of approximately two years, and the remaining expense for performance-based awards will be recognized within approximately one year. The Company also has deferred compensation plans for its Board of Directors and certain executives. Under these plans, participants can elect to invest their deferrals in the Company’s common stock. At March 31, 2013 and 2012, the number of common shares deferred under these plans was 0.8 million and 0.7 million, respectively. As these awards can be settled in cash, the Company records compensation costs each period based on the change in the Company’s stock price. For the three months ended March 31, 2013 and 2012, the Company recognized a compensation benefit of $1.6 million and expense of $0.7 million, respectively, related to the change in the Company's stock price. In 2010, the Company's Board of Directors approved long-term incentive programs for certain members of management. Payment was contingent upon the completion of a qualifying transaction and attainment of an increase in the equity value of the data center business, as defined in the plans. On January 24, 2013, the initial public offering of CyrusOne was completed, which represents a qualifying transaction requiring payment under these compensation plans. For the three months ended March 31, 2013, compensation expense of $35.5 million was recognized for these awards and other transaction-related incentives, of which $20.0 million was associated with CyrusOne employees. These payments were made in April 2013. This expense has been presented as transaction-related compensation in our Consolidated Statement of Operations for the three months ended March 31, 2013. In May 2013, additional compensation payments of $7.0 million were approved by the Board of Directors related to the success of the CyrusOne IPO.

Stock-Based and Other Compensation Plans

The Company grants stock options, stock appreciation rights (“SARs”), performance-based awards, and time-based restricted shares, some of which are cash-settled awards with the final payment indexed to the percentage change in the Company’s stock price from the date of grant.

For the three months ended March 31, 2013, the Company recognized a stock-based compensation benefit of $1.7 million, inclusive of a $3.9 million mark-to-market gain on awards indexed to the Company's stock price. For the three months ended March 31, 2012, the Company recognized stock-based compensation expense of $3.5 million, which reflected $1.5 million of mark-to-market expense. As of March 31, 2013, there was $6.9 million of unrecognized compensation expense related to these awards. The remaining compensation expense for the stock options, SARs and restricted awards is expected to be recognized over a weighted-average period of approximately two years, and the remaining expense for performance-based awards will be recognized within approximately one year.

The Company also has deferred compensation plans for its Board of Directors and certain executives. Under these plans, participants can elect to invest their deferrals in the Company’s common stock. At March 31, 2013 and 2012, the number of common shares deferred under these plans was 0.8 million and 0.7 million, respectively. As these awards can be settled in cash, the Company records compensation costs each period based on the change in the Company’s stock price. For the three months ended March 31, 2013 and 2012, the Company recognized a compensation benefit of $1.6 million and expense of $0.7 million, respectively, related to the change in the Company's stock price.

In 2010, the Company's Board of Directors approved long-term incentive programs for certain members of management. Payment was contingent upon the completion of a qualifying transaction and attainment of an increase in the equity value of the data center business, as defined in the plans. On January 24, 2013, the initial public offering of CyrusOne was completed, which represents a qualifying transaction requiring payment under these compensation plans. For the three months ended March 31, 2013, compensation expense of $35.5 million was recognized for these awards and other transaction-related incentives, of which $20.0 million was associated with CyrusOne employees. These payments were made in April 2013. This expense has been presented as transaction-related compensation in our Consolidated Statement of Operations for the three months ended March 31, 2013. In May 2013, additional compensation payments of $7.0 million were approved by the Board of Directors related to the success of the CyrusOne IPO.