Income Taxes (Details 1)	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Effective tax rate reconciliation
Combined tax at U.S. statutory federal income tax rate	35.00%	35.00%	35.00%
(Decrease) increase in taxes resulting from:
Tax-exempt income	(1.70%)	(1.70%)	(1.70%)
State and local income taxes, net of federal benefit	2.34%	2.70%	2.80%
Non-U.S. subsidiaries earnings	(5.70%)	(2.00%)	(1.80%)
Tax settlements	(0.74%)	(0.60%)	(0.20%)
Non deductible expenses	0.00%	0.00%	0.90%
U.S. Tax Act	34.80%	0.00%	0.00%
Other	(0.90%)	(0.20%)	0.00%
Actual tax rates	63.10%	33.20%	35.00%

Effective income tax rate continuing operations increase decrease in tax rate.

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U.S. Tax Act (decrease) increase impact on US Statutory Federal Income Tax Rate

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

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations applicable to state and local income tax expense (benefit), net of federal tax expense (benefit).

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to income (loss) exempt from income taxes.

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to income tax settlements. Including, but not limited to, domestic tax settlement, foreign tax settlement, state and local tax settlement, and other tax settlements.

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