SUPPLEMENTAL CONSOLIDATED BALANCE SHEETS AND STATEMENTS OF OPERATIONS INFORMATION - Schedule of Other Non-current Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Supplemental Consolidated Balance Sheet & Statement of Operations Information [Abstract]
Contingent income tax liabilities	$ 30,121	$ 39,858
Deferred rent	0	32,186
Total long-term lease obligations	5,831	12,481
Deferred income taxes	3,903	6,619
Other	5,132	9,544
Total other non-current liabilities	$ 44,987	$ 100,688

Supplemental Consolidated Balance Sheet & Statement of Operations Information [Abstract]

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Carrying amount as of the balance sheet date of the unpaid sum of the known and estimated amounts payable to satisfy all domestic and foreign income tax obligations due beyond one year or the operating cycle, whichever is longer. Alternate captions include income taxes payable, noncurrent.

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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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