Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
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-Section 50
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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Tax year that remains open to examination under enacted tax laws, in CCYY format.

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Amount of unrecognized tax benefits.

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Income Taxes Narrative (Details) - USD ($) $ in Thousands	3 Months Ended
Income Taxes Narrative (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Income Tax Examination [Line Items]
Effective Income Tax Rate Reconciliation, Percent	7.00%	36.00%
Unrecognized Tax Benefits	$ 76,120		$ 56,702
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	21.00%	35.00%
Minimum [Member]
Income Tax Examination [Line Items]
Open Tax Year	2000
Maximum [Member]
Income Tax Examination [Line Items]
Open Tax Year	2015
SSNI Plan [Member]
Income Tax Examination [Line Items]
Unrecognized Tax Benefits	$ 16,400