Supplemental Information (Supplemental Cash Flow Information) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Supplemental Information
Income taxes paid (refunded)	$ 28,926us-gaap_IncomeTaxesPaid	$ (478)us-gaap_IncomeTaxesPaid
Interest paid	2,161us-gaap_InterestPaid	1,539us-gaap_InterestPaid
Proceeds from sales of available for sale fixed maturity securities	167,206	119,011
Proceeds from sales of equity securities	66,412	144,075
Dividends declared but not paid at end of period	28,270	22,500
Purchases of common stock not paid at end of period	$ 9,840hcc_TreasuryStockPayable	$ 639hcc_TreasuryStockPayable

No authoritative reference available.

No definition available.

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Carrying value as of the balance sheet date of dividends declared but unpaid on equity securities issued by the entity and outstanding.

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The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income.

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The cash inflow associated with the sale of debt securities classified as available-for-sale securities.

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The cash inflow associated with the sale of equity securities classified as available-for-sale securities.

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