Financing Arrangements and Fair Value of Financial Instruments	6 Months Ended
Jun. 30, 2011
Financing Arrangements and Fair Value of Financial Instruments [Abstract]
Financing Arrangements and Fair Value of Financial Instruments	Note 6 — Financing Arrangements and Fair Value of Financial Instruments Our financing arrangements include $172.5 million of unsecured convertible senior notes (“Senior Notes”) and a $150.0 million revolving credit facility, of which no borrowings were outstanding at June 30, 2011. The Senior Notes bear interest at a rate of 4.0% per year, payable semi-annually in arrears on April 1 and October 1 of each year, beginning April 1, 2011. Holders may convert the Senior Notes at their option at any time prior to the close of business on the business day immediately preceding the October 1, 2017 maturity date. The conversion rate is initially 90.8893 shares of our common stock per $1,000 principal amount of Senior Notes (equivalent to an initial conversion price of $11.00 per share of common stock), subject to adjustment in certain circumstances. Upon conversion, the Senior Notes will be settled in shares of our common stock. We may not redeem the Senior Notes prior to their maturity date. Our financial instruments include cash and cash equivalents, receivables, payables and debt. We believe the carrying values of these instruments, with the exception of our Senior Notes, approximated their fair values at June 30, 2011 and December 31, 2010. The estimated fair value of our Senior Notes is $201.8 million at June 30, 2011 and $157.0 million at December 31, 2010, based on quoted market prices at these respective dates.

Note 6 — Financing Arrangements and Fair Value of Financial Instruments

Our financing arrangements include $172.5 million of unsecured convertible senior notes (“Senior Notes”) and a $150.0 million revolving credit facility, of which no borrowings were outstanding at June 30, 2011. The Senior Notes bear interest at a rate of 4.0% per year, payable semi-annually in arrears on April 1 and October 1 of each year, beginning April 1, 2011. Holders may convert the Senior Notes at their option at any time prior to the close of business on the business day immediately preceding the October 1, 2017 maturity date. The conversion rate is initially 90.8893 shares of our common stock per $1,000 principal amount of Senior Notes (equivalent to an initial conversion price of $11.00 per share of common stock), subject to adjustment in certain circumstances. Upon conversion, the Senior Notes will be settled in shares of our common stock. We may not redeem the Senior Notes prior to their maturity date.

Our financial instruments include cash and cash equivalents, receivables, payables and debt. We believe the carrying values of these instruments, with the exception of our Senior Notes, approximated their fair values at June 30, 2011 and December 31, 2010. The estimated fair value of our Senior Notes is $201.8 million at June 30, 2011 and $157.0 million at December 31, 2010, based on quoted market prices at these respective dates.