Employee Benefit Plans (Schedule of Long-term Rate of Return on Assets (Details)	12 Months Ended
Dec. 31, 2016
Fixed Income [Member]
Defined Benefit Plan Disclosure [Line Items]
Percent of Total Portfolio	48.00%
One-Year Nominal Return	4.51%
Annual Standard Deviation	4.64%
Large Cap U.S. Equities [Member]
Defined Benefit Plan Disclosure [Line Items]
Percent of Total Portfolio	10.00%
One-Year Nominal Return	7.36%
Annual Standard Deviation	16.14%
U.S. Large Cap Growth [Member]
Defined Benefit Plan Disclosure [Line Items]
Percent of Total Portfolio	18.00%
One-Year Nominal Return	7.67%
Annual Standard Deviation	17.31%
Small Cap U.S. Equities [Member]
Defined Benefit Plan Disclosure [Line Items]
Percent of Total Portfolio	8.00%
One-Year Nominal Return	8.49%
Annual Standard Deviation	20.02%
International (Developed) [Member]
Defined Benefit Plan Disclosure [Line Items]
Percent of Total Portfolio	15.00%
One-Year Nominal Return	8.89%
Annual Standard Deviation	19.35%
International (Emerging) [Member]
Defined Benefit Plan Disclosure [Line Items]
Percent of Total Portfolio	1.00%
One-Year Nominal Return	10.68%
Annual Standard Deviation	27.66%

The expected percentage of annual standard deviation on assets.

No definition available.

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- Definition

The expected percentage of one-year nominal return on assets.

+ References

No definition available.

+ Details

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- Definition

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.

+ References

No definition available.

+ Details

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- Definition

Target allocation of investments of this type to total plan assets presented on a weighted average basis.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (c)(i)
-URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e2446-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(i)
-URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920

+ Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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