|
Per Share Data and Stockholders' Equity (Details Textual)
In Millions, unless otherwise specified |
6 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
|
Jun. 30, 2013
5.0% Convertible Senior Notes [Member]
|
Aug. 31, 2012
5.0% Convertible Senior Notes [Member]
|
Jun. 30, 2013
Common Class A [Member]
|
Jun. 30, 2012
Common Class A [Member]
|
|
| Capital Structure and Per Share Data (Textual) [Abstract] | ||||
| Stated Interest rate on debt agreement | 5.00% | |||
| Antidilutive stock options excluded in computation of diluted earnings per share | 0.9 | 1.6 | ||
| Convertible senior notes maturity Year | 2029 | |||
| X | ||||||||||
|
- Details
|
| X | ||||||||||
|
- Definition
Debt instrument maturity year. No definition available.
|
| X | ||||||||||
|
- Definition
Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
|
- Definition
Contractual interest rate for funds borrowed, under the debt agreement. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|