Deferred Policy Acquisition Costs (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Movement Analysis of Deferred Policy Acquisition Costs [Roll Forward]
Balance, beginning of year	$ 185,910	$ 171,430	$ 170,579
Policy acquisition costs deferred	514,073	492,268	482,572
Amortization	(505,517)	(477,788)	(481,721)
Balance, end of year	$ 194,466	$ 185,910	$ 171,430