Retirement Benefits Net Periodic Benefit Cost (Details) (USD $) In Thousands, unless otherwise specified	6 Months Ended	12 Months Ended	6 Months Ended	12 Months Ended	6 Months Ended	12 Months Ended	3 Months Ended	6 Months Ended	3 Months Ended	6 Months Ended	3 Months Ended	6 Months Ended	3 Months Ended	6 Months Ended	3 Months Ended	6 Months Ended	3 Months Ended	6 Months Ended
Jun. 30, 2014 Qualified Pension Benefits [Member]	Dec. 31, 2013 Qualified Pension Benefits [Member]	Jun. 30, 2014 SERP Pension Benefits [Member]	Dec. 31, 2013 SERP Pension Benefits [Member]	Jun. 30, 2014 Other Benefit [Member]	Dec. 31, 2013 Other Benefit [Member]	Jun. 30, 2014 Parent Company [Member] Qualified Pension Benefits [Member]	Jun. 30, 2013 Parent Company [Member] Qualified Pension Benefits [Member]	Jun. 30, 2014 Parent Company [Member] Qualified Pension Benefits [Member]	Jun. 30, 2013 Parent Company [Member] Qualified Pension Benefits [Member]	Jun. 30, 2014 Parent Company [Member] SERP Pension Benefits [Member]	Jun. 30, 2013 Parent Company [Member] SERP Pension Benefits [Member]	Jun. 30, 2014 Parent Company [Member] SERP Pension Benefits [Member]	Jun. 30, 2013 Parent Company [Member] SERP Pension Benefits [Member]	Jun. 30, 2014 Parent Company [Member] Other Benefit [Member]	Jun. 30, 2013 Parent Company [Member] Other Benefit [Member]	Jun. 30, 2014 Parent Company [Member] Other Benefit [Member]	Jun. 30, 2013 Parent Company [Member] Other Benefit [Member]	Jun. 30, 2014 Subsidiaries [Member] Qualified Pension Benefits [Member]	Jun. 30, 2013 Subsidiaries [Member] Qualified Pension Benefits [Member]	Jun. 30, 2014 Subsidiaries [Member] Qualified Pension Benefits [Member]	Jun. 30, 2013 Subsidiaries [Member] Qualified Pension Benefits [Member]	Jun. 30, 2014 Subsidiaries [Member] SERP Pension Benefits [Member]	Jun. 30, 2013 Subsidiaries [Member] SERP Pension Benefits [Member]	Jun. 30, 2014 Subsidiaries [Member] SERP Pension Benefits [Member]	Jun. 30, 2013 Subsidiaries [Member] SERP Pension Benefits [Member]	Jun. 30, 2014 Subsidiaries [Member] Other Benefit [Member]	Jun. 30, 2013 Subsidiaries [Member] Other Benefit [Member]	Jun. 30, 2014 Subsidiaries [Member] Other Benefit [Member]	Jun. 30, 2013 Subsidiaries [Member] Other Benefit [Member]
Components of net periodic benefit cost:
Service cost	$ (8,718)	$ (19,285)	$ (521)	$ (1,498)	$ (56)	$ (134)	$ 4,206	$ 4,934	$ 8,718	$ 9,643	$ 261	$ 375	$ 521	$ 749	$ 26	$ 32	$ 56	$ 67	$ 4,206	$ 4,934	$ 8,718	$ 9,643	$ 261	$ 375	$ 521	$ 749	$ 26	$ 32	$ 56	$ 67
Interest cost	(14,020)	(24,754)	(1,155)	(2,045)	(342)	(664)	6,965	6,182	14,020	12,377	577	511	1,155	1,022	159	155	342	332	6,965	6,182	14,020	12,377	577	511	1,155	1,022	159	155	342	332
Expected return on plan assets							(10,511)	(9,696)	(21,232)	(19,548)	0	0	0	0	(134)	(109)	(267)	(218)	(10,708)	(10,094)	(21,626)	(20,343)	0	0	0	0	(134)	(109)	(267)	(218)
Amortization of prior service cost							(495)	(495)	(990)	(990)	11	(4)	22	(9)	0	0	(197)	0	(393)	(393)	(786)	(787)	11	(4)	22	(8)	1	8	2	14
Amortization of net loss (gain)							0	794	0	1,444	228	365	456	731	(130)	18	0	34	3,359	5,221	6,597	10,306	365	548	730	1,096	(208)	(108)	(352)	(142)
Defined Benefit Plan, Net Periodic Benefit Cost							$ 165	$ 1,719	$ 516	$ 2,926	$ 1,077	$ 1,247	$ 2,154	$ 2,493	$ (79)	$ 96	$ (66)	$ 215	$ 3,429	$ 5,850	$ 6,923	$ 11,196	$ 1,214	$ 1,430	$ 2,428	$ 2,859	$ (156)	$ (22)	$ (219)	$ 53

The amount of gains or losses recognized in net periodic benefit cost.

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- Definition

The amount of the prior service cost or credit recognized in net periodic benefit cost relating to benefit changes attributable to plan participants' prior service pursuant to a plan amendment or a plan initiation.

+ References

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An amount calculated as a basis for determining the extent of delayed recognition of the effects of changes in the fair value of assets. The expected return on plan assets is determined based on the expected long-term rate of return on plan assets and the market-related value of plan assets.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 30

-Glossary Expected Return on Plan Assets

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 60

-Glossary Expected Return on Plan Assets

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (h)(3)

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The increase in a defined benefit pension plan's projected benefit obligation or a defined benefit postretirement plan's accumulated postretirement benefit obligation due to the passage of time.

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The total amount of net periodic benefit cost for defined benefit plans for the period. Periodic benefit costs include the following components: service cost, interest cost, expected return on plan assets, gain (loss), prior service cost or credit, transition asset or obligation, and gain (loss) due to settlements or curtailments.

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- Definition

The actuarial present value of benefits attributed by the pension benefit formula to services rendered by employees during the period. The portion of the expected postretirement benefit obligation attributed to employee service during the period. The service cost component is a portion of the benefit obligation and is unaffected by the funded status of the plan.

+ 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 (h)(1)

-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 Service Cost (Component of Net Periodic Pension Cost)

-URI http://asc.fasb.org/extlink&oid=6525008

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (a)(1)

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

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