Share-Based Compensation (Summary of Grant Date Fair Value of Awards) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Options	$ 53	$ 633	$ 12,580	$ 3,507
Restricted stock	1,247	1,582	3,361	4,182
Total	$ 1,300	$ 2,215	$ 15,941	$ 7,689

Total fair value of options and restricted stock awarded during period.

No definition available.

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