Deferred Policy Acquisition Costs (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
DeferredPolicyAcquisitionCostsDisclosuresAbstract
Balance, beginning of year	$ 967,558	$ 906,814
Balance, end of year	$ 967,558	$ 906,814

Net amount of deferred policy acquisition costs capitalized on contracts remaining in force as of the balance sheet date.

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+ Details