Loss Reserves (Details) (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2014		Sep. 30, 2013
Loss Reserve [Roll Forward]
Reserve at beginning of period	$ 3,061,401		$ 4,056,843
Less reinsurance recoverable	64,085		104,848
Net reserve at beginning of period	2,997,316		3,951,995
Losses and LAE incurred in respect of default notices related to:
Current year	454,390		686,454
Prior years	(75,387)	[1],[2]	(43,783)	[1],[2]
Subtotal	379,003		642,671
Losses and LAE paid in respect of default notices related to:
Current year	11,574		28,792
Prior years	895,061		1,286,833
Reinsurance terminations	0	[3]	(3,332)	[3]
Subtotal	906,635		1,312,293
Net reserve at end of period	2,469,684		3,282,373
Plus reinsurance recoverables	57,898		70,621
Reserve at end of period	$ 2,527,582		$ 3,352,994

[1] A negative number for prior year loss development indicates a redundancy of prior year loss reserves, and a positive number indicates a deficiency of prior year loss reserves.

[2] A negative number for prior year losses incurred indicates a redundancy of prior year loss reserves and a positive number for prior year losses incurred indicates a deficiency of prior year loss reserves.

[3] In a termination, the reinsurance agreement is cancelled, with no future premium ceded and funds for any incurred but unpaid losses transferred to us. The transferred funds result in an increase in our investment portfolio (including cash and cash equivalents) and a decrease in net losses paid (reduction to losses incurred). In addition, there is an offsetting decrease in the reinsurance recoverable (increase in losses incurred), and thus there is no net impact to losses incurred.