Schedule 2 HCCIH Financial Statements (Details Textuals) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Condensed Financial Information of Parent Company Only Disclosure [Abstract]
Interest rate on intercompany loan	6.25%hcc_InterestRateOnIntercompanyLoan
Parent intercompany loan from subsidiary		$ 25.0
Dividends received from subsidiary	377.2	328.2	270.3
Dividend received including fixed income securities and related accrued interest	$ 332.9	$ 317.2	$ 262.8
Interest rate on loan from subsidiary		0.0245%hcc_InterestRateOnLoanFromSubsidiary

Interest Rate On Intercompany Loan

No definition available.

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- Definition

Interest rate on loan from subsidiary

+ References

No definition available.

+ Details

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- Definition

This element represents disclosure of the aggregate cash dividends paid to the entity by consolidated subsidiaries.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 235

-Section S99

-Paragraph 2

-Subparagraph (SX 210.9-06)

-URI http://asc.fasb.org/extlink&oid=6882215&loc=d3e537971-122884

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 06

-Article 9

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph b

-Article 12

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 3

-Subparagraph (SX 210.12-04.(b))

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24072-122690

+ Details

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- Definition

The cash inflow from an entity that is affiliated with the entity by means of direct or indirect ownership.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 14

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3255-108585

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

-URI http://asc.fasb.org/extlink&oid=6513228

+ Details

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- Definition

Cash received for dividends and interest on the entity's equity and debt investments during the current period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 25

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3536-108585

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Balance Type:	debit
Period Type:	duration