| **Stockholders' Equity (Tables)**                                                              | 6 Months Ended                                                                                                                                                                                                                                                                                                                                                                             |
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| **Stockholders' Equity Note [Abstract]**                                                       |                                                                                                                                                                                                                                                                                                                                                                                       |
| Schedule of Share-based Compensation, Restricted Stock Units Award Activity [Table Text Block] |      Weighted      Average      Grant Date   Shares Fair Value  Nonvested at January 1, 2013 1,127$9.59   Granted 664$8.22   Vested (119)$7.87   Forfeited (3)$9.60  Nonvested at June 30, 2013 1,669$9.15  |
| Schedule Of Share-based Compensation [Table Text Block]                                        |    2013 2012  Share-based compensation expense$ 3,094  2,831  Adjustment to fair value of liability classified awards  (188)  (236)    Total share-based compensation expense$ 2,906  2,595                                                                                                                     |

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| - Definition
Table of components of share-based compensation expense.
+ References
No definition available.
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| - Definition
Tabular disclosure of the number and weighted-average grant date fair value for restricted stock units that were outstanding at the beginning and end of the year, and the number of restricted stock units that were granted, vested, or forfeited during the year.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901
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