Supplemental Consolidated Balance Sheet Information (Components Of Prepaid Expenses And Other Current Assets) (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Supplemental Consolidated Balance Sheet Information [Abstract]
Notes receivable - current	$ 2,227	$ 2,636
Prepaid recruiting and retention incentives - current	9,444	9,173
Other prepaid expenses and other current assets	18,975	17,953
Prepaid expenses and other current assets	$ 30,646	$ 29,762

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Amounts due from parties associated with the reporting entity as evidenced by a written promise to pay, due within 1 year (or 1 business cycle).

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