Investments (Gross Unrealized Losses on Investments, By Category and Length of Time) (Details) (USD $) | 12 Months Ended |
In Thousands, unless otherwise specified | Dec. 31, 2013 | Dec. 31, 2012 |
Fixed Maturity Securities [Member] | ' | ' |
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract] | ' | ' |
Available for sale, continuous unrealized loss position, less than 12 months, fair value | $11,635,998 | $2,716,900 |
Available for sale, continuous unrealized loss position, less than 12 months, unrealized losses | -741,947 | -33,982 |
Available for sale, continuous unrealized loss position, 12 months or more, fair value | 1,097,643 | 443,515 |
Available for sale, continuous unrealized loss position, 12 months or more, unrealized losses | -104,035 | -33,919 |
Available for sale, continuous unrealized loss position, total, fair value | 12,733,641 | 3,160,415 |
Available for sale, continuous unrealized loss position, total, unrealized losses | -845,982 | -67,901 |
Equity Securities, Available For Sale [Member] | Services [Member] | ' | ' |
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract] | ' | ' |
Available for sale, continuous unrealized loss position, less than 12 months, fair value | ' | 0 |
Available for sale, continuous unrealized loss position, less than 12 months, unrealized losses | ' | 0 |
Available for sale, continuous unrealized loss position, 12 months or more, fair value | ' | 8,722 |
Available for sale, continuous unrealized loss position, 12 months or more, unrealized losses | ' | -1,403 |
Available for sale, continuous unrealized loss position, total, fair value | ' | 8,722 |
Available for sale, continuous unrealized loss position, total, unrealized losses | ' | -1,403 |
United States Government Full Faith and Credit [Member] | Fixed Maturity Securities [Member] | ' | ' |
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract] | ' | ' |
Available for sale, continuous unrealized loss position, less than 12 months, fair value | 32,969 | ' |
Available for sale, continuous unrealized loss position, less than 12 months, unrealized losses | -2,294 | ' |
Available for sale, continuous unrealized loss position, 12 months or more, fair value | 0 | ' |
Available for sale, continuous unrealized loss position, 12 months or more, unrealized losses | 0 | ' |
Available for sale, continuous unrealized loss position, total, fair value | 32,969 | ' |
Available for sale, continuous unrealized loss position, total, unrealized losses | -2,294 | ' |
United States Government Sponsored Agencies [Member] | Fixed Maturity Securities [Member] | ' | ' |
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract] | ' | ' |
Available for sale, continuous unrealized loss position, less than 12 months, fair value | 692,320 | 973,728 |
Available for sale, continuous unrealized loss position, less than 12 months, unrealized losses | -88,671 | -3,468 |
Available for sale, continuous unrealized loss position, 12 months or more, fair value | 467,309 | 0 |
Available for sale, continuous unrealized loss position, 12 months or more, unrealized losses | -32,691 | 0 |
Available for sale, continuous unrealized loss position, total, fair value | 1,159,629 | 973,728 |
Available for sale, continuous unrealized loss position, total, unrealized losses | -121,362 | -3,468 |
United States Municipalities, States and Territories [Member] | Fixed Maturity Securities [Member] | ' | ' |
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract] | ' | ' |
Available for sale, continuous unrealized loss position, less than 12 months, fair value | 614,056 | 24,393 |
Available for sale, continuous unrealized loss position, less than 12 months, unrealized losses | -39,074 | -125 |
Available for sale, continuous unrealized loss position, 12 months or more, fair value | 0 | 0 |
Available for sale, continuous unrealized loss position, 12 months or more, unrealized losses | 0 | 0 |
Available for sale, continuous unrealized loss position, total, fair value | 614,056 | 24,393 |
Available for sale, continuous unrealized loss position, total, unrealized losses | -39,074 | -125 |
Foreign Government Obligations [Member] | Fixed Maturity Securities [Member] | ' | ' |
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract] | ' | ' |
Available for sale, continuous unrealized loss position, less than 12 months, fair value | 26,298 | ' |
Available for sale, continuous unrealized loss position, less than 12 months, unrealized losses | -3,462 | ' |
Available for sale, continuous unrealized loss position, 12 months or more, fair value | 0 | ' |
Available for sale, continuous unrealized loss position, 12 months or more, unrealized losses | 0 | ' |
Available for sale, continuous unrealized loss position, total, fair value | 26,298 | ' |
Available for sale, continuous unrealized loss position, total, unrealized losses | -3,462 | ' |
Corporate Securities [Member] | Fixed Maturity Securities [Member] | Finance, Insurance and Real Estate [Member] | ' | ' |
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract] | ' | ' |
Available for sale, continuous unrealized loss position, less than 12 months, fair value | 1,690,846 | 177,962 |
Available for sale, continuous unrealized loss position, less than 12 months, unrealized losses | -92,426 | -4,126 |
Available for sale, continuous unrealized loss position, 12 months or more, fair value | 153,037 | 85,709 |
Available for sale, continuous unrealized loss position, 12 months or more, unrealized losses | -12,873 | -8,438 |
Available for sale, continuous unrealized loss position, total, fair value | 1,843,883 | 263,671 |
Available for sale, continuous unrealized loss position, total, unrealized losses | -105,299 | -12,564 |
Corporate Securities [Member] | Fixed Maturity Securities [Member] | Manufacturing, Construction and Mining [Member] | ' | ' |
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract] | ' | ' |
Available for sale, continuous unrealized loss position, less than 12 months, fair value | 3,370,775 | 426,120 |
Available for sale, continuous unrealized loss position, less than 12 months, unrealized losses | -191,245 | -4,303 |
Available for sale, continuous unrealized loss position, 12 months or more, fair value | 93,608 | 21,975 |
Available for sale, continuous unrealized loss position, 12 months or more, unrealized losses | -16,088 | -1,281 |
Available for sale, continuous unrealized loss position, total, fair value | 3,464,383 | 448,095 |
Available for sale, continuous unrealized loss position, total, unrealized losses | -207,333 | -5,584 |
Corporate Securities [Member] | Fixed Maturity Securities [Member] | Utilities and Related Sectors [Member] | ' | ' |
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract] | ' | ' |
Available for sale, continuous unrealized loss position, less than 12 months, fair value | 1,829,868 | 221,044 |
Available for sale, continuous unrealized loss position, less than 12 months, unrealized losses | -102,758 | -5,187 |
Available for sale, continuous unrealized loss position, 12 months or more, fair value | 83,550 | 39,224 |
Available for sale, continuous unrealized loss position, 12 months or more, unrealized losses | -11,547 | -4,212 |
Available for sale, continuous unrealized loss position, total, fair value | 1,913,418 | 260,268 |
Available for sale, continuous unrealized loss position, total, unrealized losses | -114,305 | -9,399 |
Corporate Securities [Member] | Fixed Maturity Securities [Member] | Wholesale/Retail Trade [Member] | ' | ' |
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract] | ' | ' |
Available for sale, continuous unrealized loss position, less than 12 months, fair value | 428,407 | 101,790 |
Available for sale, continuous unrealized loss position, less than 12 months, unrealized losses | -25,189 | -784 |
Available for sale, continuous unrealized loss position, 12 months or more, fair value | 17,687 | 10,250 |
Available for sale, continuous unrealized loss position, 12 months or more, unrealized losses | -1,992 | -208 |
Available for sale, continuous unrealized loss position, total, fair value | 446,094 | 112,040 |
Available for sale, continuous unrealized loss position, total, unrealized losses | -27,181 | -992 |
Corporate Securities [Member] | Fixed Maturity Securities [Member] | Services, Media and Other [Member] | ' | ' |
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract] | ' | ' |
Available for sale, continuous unrealized loss position, less than 12 months, fair value | 834,699 | 264,421 |
Available for sale, continuous unrealized loss position, less than 12 months, unrealized losses | -51,508 | -3,085 |
Available for sale, continuous unrealized loss position, 12 months or more, fair value | 107,242 | 0 |
Available for sale, continuous unrealized loss position, 12 months or more, unrealized losses | -10,403 | 0 |
Available for sale, continuous unrealized loss position, total, fair value | 941,941 | 264,421 |
Available for sale, continuous unrealized loss position, total, unrealized losses | -61,911 | -3,085 |
Corporate Securities [Member] | Fixed Maturity Securities [Member] | Insurance [Member] | ' | ' |
Held-to-maturity Securities, Continuous Unrealized Loss Position [Abstract] | ' | ' |
Held for investment, continuous unrealized loss position, less than 12 months, fair value | 0 | 0 |
Held for investment, continuous unrealized loss position, less than 12 months, unrealized losses | 0 | 0 |
Held for investment, continuous unrealized loss position, 12 months or more, fair value | 60,840 | 61,521 |
Held for investment, continuous unrealized loss position, 12 months or more, unrealized losses | -15,415 | -14,567 |
Held for investment, continuous unrealized loss position, total, fair value | 60,840 | 61,521 |
Held for investment, continuous unrealized loss position, total, unrealized losses | -15,415 | -14,567 |
Residential Mortgage Backed Securities [Member] | Fixed Maturity Securities [Member] | ' | ' |
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract] | ' | ' |
Available for sale, continuous unrealized loss position, less than 12 months, fair value | 309,599 | 220,622 |
Available for sale, continuous unrealized loss position, less than 12 months, unrealized losses | -41,080 | -8,679 |
Available for sale, continuous unrealized loss position, 12 months or more, fair value | 31,739 | 260,226 |
Available for sale, continuous unrealized loss position, 12 months or more, unrealized losses | -2,103 | -19,049 |
Available for sale, continuous unrealized loss position, total, fair value | 341,338 | 480,848 |
Available for sale, continuous unrealized loss position, total, unrealized losses | -43,183 | -27,728 |
Commercial Mortgage Backed Securities [Member] | Fixed Maturity Securities [Member] | ' | ' |
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract] | ' | ' |
Available for sale, continuous unrealized loss position, less than 12 months, fair value | 1,450,143 | 161,582 |
Available for sale, continuous unrealized loss position, less than 12 months, unrealized losses | -83,814 | -1,983 |
Available for sale, continuous unrealized loss position, 12 months or more, fair value | 51,099 | 0 |
Available for sale, continuous unrealized loss position, 12 months or more, unrealized losses | -6,001 | 0 |
Available for sale, continuous unrealized loss position, total, fair value | 1,501,242 | 161,582 |
Available for sale, continuous unrealized loss position, total, unrealized losses | -89,815 | -1,983 |
Other Asset Backed Securities [Member] | Fixed Maturity Securities [Member] | ' | ' |
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract] | ' | ' |
Available for sale, continuous unrealized loss position, less than 12 months, fair value | 356,018 | 145,238 |
Available for sale, continuous unrealized loss position, less than 12 months, unrealized losses | -20,426 | -2,242 |
Available for sale, continuous unrealized loss position, 12 months or more, fair value | 92,372 | 26,131 |
Available for sale, continuous unrealized loss position, 12 months or more, unrealized losses | -10,337 | -731 |
Available for sale, continuous unrealized loss position, total, fair value | 448,390 | 171,369 |
Available for sale, continuous unrealized loss position, total, unrealized losses | ($30,763) | ($2,973) |