Income Taxes (Details 1)	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Effective tax rate reconciliation
U.S. statutory federal income tax rate	21.00%	21.00%	21.00%
(Decrease) increase in taxes resulting from:
Tax-exempt income	(4.10%)	(1.90%)	(1.70%)
State and local income taxes, net of federal benefit	3.70%	2.80%	2.80%
Non-U.S. subsidiaries' earnings	2.40%	(0.50%)	(1.00%)
Tax settlements	(0.30%)	(0.30%)	(1.90%)
U.S. Tax Act and related adjustments	0.00%	0.00%	(4.30%)
Valuation allowances	4.00%	(0.20%)	0.50%
Other	0.30%	(1.10%)	(0.60%)
Actual tax rates	27.00%	19.80%	14.80%

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

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Adjustments related to the U.S. Tax Act that (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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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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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/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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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 changes in the valuation allowance for deferred tax assets.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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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 statutory income tax expense (benefit) outside of the country of domicile.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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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 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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