Supplemental Consolidated Balance Sheet Information (Components Of Other Non-Current Liabilities) (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Supplemental Consolidated Balance Sheet Information [Abstract]
Deferred acquisition liabilities - non-current	$ 1,154	$ 943
Deferred rent - non-current	26,214	19,776
Other non-current liabilities	8,466	11,860
Total other non-current liabilities	$ 35,834	$ 32,579

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Amount of liability recognized arising from contingent consideration in a business combination, expected to be settled beyond one year or the normal operating cycle, if longer.

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For a classified balance sheet, the cumulative difference between the rental income or payments required by a lease agreement and the rental income or expense recognized on a straight-line basis, or other systematic and rational basis more representative of the time pattern in which use or benefit is granted or derived from the leased property, expected to be recognized in income or expense, by the lessor or lessee, respectively, more than one year after the balance sheet date.

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Amount of liabilities classified as other, due after one year or the normal operating cycle, if longer.

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Obligations not otherwise itemized or categorized in the footnotes to the financial statements that are expected to be paid after one year (or the normal operating cycle, if longer), from the balance sheet date.

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