Defined Contribution Plan, Employer Discretionary Contribution Percent

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- Definition

Amount of actuarial present value of benefits attributed to service rendered by employee for defined benefit plan.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e1928-114920

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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.

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- Definition

Amount of cost for defined contribution plan.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 70
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942

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- Definition

Amount of discretionary contributions made by an employer to a defined contribution plan.

+ References

No definition available.

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- Definition

Percentage employer matches of the employee's percentage contribution matched.

+ References

No definition available.

+ Details

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- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

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- Definition

Amount of contributions made to multiemployer plan by employer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 80
-Section 50
-Paragraph 9
-URI http://asc.fasb.org/extlink&oid=65877416&loc=SL14450691-114947

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 80
-Section 50
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=65877416&loc=SL14450702-114947

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 80
-Section 50
-Paragraph 5
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-URI http://asc.fasb.org/extlink&oid=65877416&loc=SL14450657-114947

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- Definition

Amount of the obligation recognized by withdrawing from a pension or postretirement benefit plan to which two or more unrelated employers contribute where assets contributed by one participating employer may be used to provide benefits to employees of other participating employers.

+ References

No definition available.

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Other Employee Benefit Plans (Narrative) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Matching contribution (as a percent)	6.00%
Discretionary contribution to plan	$ 10,445,000	$ 0	$ 9,499,000
Payments and costs of plan	$ 20,655,000	9,888,000	17,687,000
Minimum
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Discretionary matching contribution (as a percent)	1.00%
Maximum
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Discretionary matching contribution (as a percent)	6.00%
Retiree Health Benefit Act of 1992
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Contributions to multi-employer plan	$ 6,829,000	7,647,000	8,455,000
Combined fund obligation	70,859,000
Multiemployer Plans
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Letters of credit outstanding	19,860,000	20,983,000	$ 19,170,000
Long-Term Disability
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Combined total obligation	$ 12,022,000	$ 15,315,000