Debt Long Term Debt (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Debt Instrument [Line Items]
Long-term Debt Including Related Party, Gross	$ 1,520,000	$ 1,525,000
Add: Unamortized premium	5,677	5,824
Less: Short-term borrowings and current portion of long-term debt	(30,000)us-gaap_DebtCurrent	(5,000)us-gaap_DebtCurrent
Long-term debt (including related party)	1,495,677	1,525,824
$200 million revolving credit facility, LIBOR plus 1.25%-1.75%, due December 2019 \| Revolving Credit Facility [Member] \| Line of Credit [Member]
Debt Instrument [Line Items]
Long-term Debt Including Related Party, Gross	0	0
7.375% Senior notes, due May 2018 \| Senior notes (Level 1)
Debt Instrument [Line Items]
Long-term Debt Including Related Party, Gross	345,000	345,000
6.625% Senior notes, due June 2021, $75 million related party \| Senior notes (Level 1)
Debt Instrument [Line Items]
Long-term Debt Including Related Party, Gross	400,000	400,000
6.375% Senior notes, due October 2022 \| Senior notes (Level 1)
Debt Instrument [Line Items]
Long-term Debt Including Related Party, Gross	525,000	525,000
KOREA, REPUBLIC OF \| Revolving credit facility due June 2016 [Member] \| Revolving Credit Facility [Member] \| Line of Credit [Member]
Debt Instrument [Line Items]
Long-term Debt Including Related Party, Gross	30,000	0
KOREA, REPUBLIC OF \| Term loan, LIBOR plus 3.70%, due June 2016 (2) \| Subsidiary Term Loans [Member]
Debt Instrument [Line Items]
Long-term Debt Including Related Party, Gross	70,000	70,000
KOREA, REPUBLIC OF \| Term loan, foreign currency funding-linked base rate plus 1.80%, due March 2017 (3) \| Subsidiary Term Loans [Member]
Debt Instrument [Line Items]
Long-term Debt Including Related Party, Gross	80,000	80,000
KOREA, REPUBLIC OF \| Term loan, LIBOR plus 3.70%, due July 2017 (1) \| Subsidiary Term Loans [Member]
Debt Instrument [Line Items]
Long-term Debt Including Related Party, Gross	0	30,000
KOREA, REPUBLIC OF \| Term loan, foreign currency funding-linked base rate plus 1.75%, due September 2017 (4) \| Subsidiary Term Loans [Member]
Debt Instrument [Line Items]
Long-term Debt Including Related Party, Gross	0	5,000
KOREA, REPUBLIC OF \| Term loan, LIBOR plus 3.70%, due December 2019 (5) \| Subsidiary Term Loans [Member]
Debt Instrument [Line Items]
Long-term Debt Including Related Party, Gross	70,000	70,000
TAIWAN, PROVINCE OF CHINA \| Revolving credit facility, TAIFX plus a bank-determined spread, due April 2015 (Taiwan) (6) \| Revolving Credit Facility [Member] \| Line of Credit [Member]
Debt Instrument [Line Items]
Long-term Debt Including Related Party, Gross	$ 0	$ 0

Amount of long-term debt, including related party debt, before deduction of unamortized discount or premium.

No definition available.

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- Definition

Non current long-term debt including related party.

+ References

No definition available.

+ Details

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- Definition

Amount of short-term debt and current maturity of long-term debt and capital lease obligations due within one year or the normal operating cycle, if longer.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.19,20)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19

-Article 5

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- Definition

The amount of debt premium that was originally recognized at the issuance of the instrument that has yet to be amortized.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 1A

-URI http://asc.fasb.org/extlink&oid=6451184&loc=d3e28541-108399

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 55

-Paragraph 8

-URI http://asc.fasb.org/extlink&oid=34725769&loc=d3e28878-108400

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