Pension and Severance Plans (Defined Benefit Plans - Expected future contributions and other disclosures) (Details) (USD $)	3 Months Ended	12 Months Ended
Dec. 31, 2013	Dec. 31, 2014	Dec. 31, 2013
Defined Benefit Plan, Estimated Future Benefit Payments [Abstract]
Employer contributions		$ 3,756,000	$ 1,120,000
Defined Benefit Plan, Estimated Future Employer Contributions in Next Fiscal Year	1,700,000
2013		1,384,000
2014		2,019,000
2015		1,869,000
2016		2,430,000
2017		3,710,000
2018 to 2022		$ 28,694,000

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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (b)(3)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

+ Details

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

- Details

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

- Definition

Amount of benefits from a defined benefit plan expected to be paid in the five fiscal years after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References