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

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- Definition

The amount of decrease that is related to an event that significantly reduces the expected years of future service of present employees or eliminates for a significant number of employees the accrual of defined benefits for some or all of their future services.

+ 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 (a)(10)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Plan Curtailment
-URI http://asc.fasb.org/extlink&oid=6520938

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 30
-Section 15
-Paragraph 6
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=7577095&loc=d3e8001-114927

+ 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

Amount of employer's best estimate of contributions expected to be paid to the plan in the current remaining fiscal period.

+ References

No definition available.

+ Details

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- Details

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- Details

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Employee Benefit Plans - Narrative (Details) - USD ($)	3 Months Ended		9 Months Ended
Employee Benefit Plans - Narrative (Details) - USD ($)	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
SERPs
Defined Benefit Plan Disclosure [Line Items]
Contributions to benefit plan			$ 800,000
Estimated future contributions			300,000
Defined benefit plans
Defined Benefit Plan Disclosure [Line Items]
Contributions to benefit plan			7,600,000
Defined Benefit Plan, Curtailments	$ 0	$ 0	0	$ 1,080,000
Minimum \| Defined benefit plans
Defined Benefit Plan Disclosure [Line Items]
Estimated future contributions			1,000,000
Maximum \| Defined benefit plans
Defined Benefit Plan Disclosure [Line Items]
Estimated future contributions			$ 2,000,000