- Schedule of Reconciliation of the U.S. Statutory Income Tax Rate to the Effective Tax Rate (Details)	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Effective Income Tax Rate Reconciliation, Percent [Abstract]
U.S. federal income tax rate	35.00%	35.00%	35.00%
State taxes, net of federal benefit	4.20%	1.50%	1.60%
Tax-exempt income	(5.60%)	(5.10%)	(3.70%)
Tax credits	(9.40%)	(6.80%)	(3.60%)
Foreign tax differential	(9.60%)	(8.50%)	(5.90%)
Tax Refund	(2.80%)	(0.00%)	(0.00%)
Litigation Expense	2.70%	1.30%	0.00%
Other, net	(0.70%)	(0.30%)	(0.30%)
Effective tax rate	13.80%	17.10%	23.10%

Effective Income Tax Rate Reconciliation, Litigation Expense, Percent

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
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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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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

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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 tax credits. Including, but not limited to, research credit, foreign tax credit, investment tax credit, and other tax credits.

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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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