Employee Benefit Plans (Multi-Employer Pension And Other Postretirement Benefit Plans) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Multiemployer Plans [Line Items]
Contribution Amount	$ 2,748	$ 3,011	$ 3,195
WSC [Member] \| MM&P [Member]
Multiemployer Plans [Line Items]
Contribution Amount	609	664	996
Surcharge Imposed	No
Expiration Date, First	Sep. 30, 2025
Expiration Date, Last	Sep. 30, 2025
WSC [Member] \| MEBA [Member]
Multiemployer Plans [Line Items]
Contribution Amount	272	259	311
Surcharge Imposed	No
Expiration Date	Sep. 30, 2020
WSC [Member] \| ARA [Member]
Multiemployer Plans [Line Items]
Contribution Amount			2
Surcharge Imposed	No
WSC [Member] \| SPP [Member]
Multiemployer Plans [Line Items]
Contribution Amount	86	80	81
Surcharge Imposed	No
Expiration Date, First	Sep. 30, 2017
Expiration Date, Last	Dec. 31, 2016
SCI [Member] \| MM&P [Member]
Multiemployer Plans [Line Items]
Contribution Amount	378	468	298
Expiration Date	Jun. 30, 2027
SCI [Member] \| MEBA [Member]
Multiemployer Plans [Line Items]
Contribution Amount	127	125	68
Expiration Date	Jun. 30, 2017
SCI [Member] \| SPP [Member]
Multiemployer Plans [Line Items]
Contribution Amount	85	72	20
Expiration Date	Jun. 30, 2017
CGL [Member] \| MM&P [Member]
Multiemployer Plans [Line Items]
Contribution Amount	790	950	1,039
Expiration Date, First	Sep. 30, 2025
Expiration Date, Last	Jun. 30, 2020
CGL [Member] \| MEBA [Member]
Multiemployer Plans [Line Items]
Contribution Amount	257	249	242
Expiration Date, First	Sep. 30, 2020
Expiration Date, Last	Jun. 30, 2020
CGL [Member] \| ARA [Member]
Multiemployer Plans [Line Items]
Contribution Amount	54	54	52
Expiration Date, First	Sep. 30, 2015
Expiration Date, Last	Jun. 30, 2017
CGL [Member] \| SPP [Member]
Multiemployer Plans [Line Items]
Contribution Amount	$ 90	$ 90	$ 86
Expiration Date, First	Dec. 31, 2016
Expiration Date, Last	Jun. 30, 2017

Amount of contributions made to multiemployer plans by the employer. A multiemployer plan is 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.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 80

-Section 50

-Paragraph 11

-URI http://asc.fasb.org/extlink&oid=14450570&loc=SL14450702-114947

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 80

-Section 50

-Paragraph 9

-URI http://asc.fasb.org/extlink&oid=14450570&loc=SL14450691-114947

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 80

-Section 50

-Paragraph 5

-Subparagraph (e)(1)

-URI http://asc.fasb.org/extlink&oid=14450570&loc=SL14450657-114947

+ Details

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

- Definition

Expiration date of the collective bargaining arrangement requiring contributions to the multiemployer plan, in CCYY-MM-DD format. A multiemployer plan is 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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 80

-Section 50

-Paragraph 5

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=14450570&loc=SL14450657-114947

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Expiration date of the collective bargaining arrangement requiring contributions to the multiemployer plan that will expire first in a group of associated collective bargaining arrangements, in CCYY-MM-DD format. A multiemployer plan is 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

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Expiration date of the collective bargaining arrangement requiring contributions to the multiemployer plan that will expire last in a group of associated collective bargaining arrangements, in CCYY-MM-DD format. A multiemployer plan is 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

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Indicate whether the employer paid a surcharge to the 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. The acceptable values are "no", "yes", and "NA".

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 80

-Section 50

-Paragraph 5

-Subparagraph (f)(2)

-URI http://asc.fasb.org/extlink&oid=14450570&loc=SL14450657-114947

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	us-types:surchargeItemType
Balance Type:	na
Period Type:	duration

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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Namespace Prefix:
Data Type:	na
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Period Type: