Defined benefit plan actual percentage return on plan assets

No definition available.

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Period Type:	duration

- Definition

Retirement eligible age for participation

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

No authoritative reference available.

+ References

No definition available.

+ Details

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- Details

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- Definition

Amount included in accumulated other comprehensive income (AOCI) expected to be recognized as components of net periodic benefit cost for the fiscal year that follows the most recent annual statement of financial position, including gain (loss), prior service cost (credit), and transition asset (obligation).

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The increase in the fair value of plan assets from contributions made by the employer.

+ References

+ Details

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Balance Type:	debit
Period Type:	duration

- Definition

A general description of the direction and pattern of change in the assumed trend rate(s) starting after one year from the current statement of financial position date.

+ References

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

The assumed health care cost trend rate for the next year used to measure the expected cost of benefits covered by the plan (gross eligible charges). This is based upon the annual rate of change in the cost of health care benefits currently provided by the postretirement benefit plan, due to factors other than changes in the composition of the plan population by age and dependency status.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (l)

-URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Health Care Cost Trend Rate

-URI http://asc.fasb.org/extlink&oid=6514820

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Target allocation maximum percentage 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 1

-Subparagraph (d)(i)

-URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920

Reference 2: 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=28361610&loc=d3e2446-114920

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Target allocation minimum percentage 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 1

-Subparagraph (d)(i)

-URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920

Reference 2: 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=28361610&loc=d3e2446-114920

+ Details

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- Definition

The ultimate trend rate for health care costs.

+ References

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The amount of the cost recognized during the period for defined contribution plans.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 70

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6414718&loc=d3e28014-114942

+ Details

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Retirement Plans (Details Textuals) (USD $)	12 Months Ended
Retirement Plans (Details Textuals) (USD $)	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Retirements Plans [Line Items]
Retirement eligible age for participation	55
Years eligble of service for participation	5
Actual return on plan assets percentage	18.54%	12.46%
Contribution made by the Corporation to pension plan	$ 28,000,000	$ 40,000,000
Total expense related to 401(k)	11,000,000	10,000,000	9,000,000
Acturial Losses [Member]
Retirements Plans [Line Items]
Amounts to be amortized from AOCI next fiscal year	1,000,000
Equity Securities [Member]
Retirements Plans [Line Items]
Plan asset allocation minimum percentage	55.00%
Plan asset allocation maximum percentage	65.00%
Debt Securities [Member]
Retirements Plans [Line Items]
Plan asset allocation minimum percentage	35.00%
Plan asset allocation maximum percentage	45.00%
CashAndCashEquivalentsMember
Retirements Plans [Line Items]
Plan asset allocation minimum percentage	0.00%
Plan asset allocation maximum percentage	5.00%
CashAndCashEquivalentsMember \| Prior Service Cost [Member]
Retirements Plans [Line Items]
Amounts to be amortized from AOCI next fiscal year	$ 100,000
Alternative Securities [Member]
Retirements Plans [Line Items]
Plan asset allocation minimum percentage	0.00%
Plan asset allocation maximum percentage	15.00%
Pre-65 Health Care Trend Rate [Member]
Retirements Plans [Line Items]
Health care trend rate assumption	9.50%
Change in assumption	.05% lower in each succeeding year
Ultimate future rate	5.00%
Post-65 Health Care Trend [Member]
Retirements Plans [Line Items]
Health care trend rate assumption	9.00%
Change in assumption	.05% lower in each succeeding year
Ultimate future rate	5.00%