Investments - Schedule of Unrealized Loss on Investments (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Schedule of Available-for-sale Securities [Line Items]
Less than 12 months, Fair Vaule	$ 207,361	$ 46,905
Securities Available for Sale, Continuous Unrealized Loss Position, Less Than 12 Months, Aggregate Losses	8,678	265
12 months or more, Fair Value	28,605	14,655
Securities Available for Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Losses	2,655	477
Total, Fair Value	235,966	61,560
Securities Available for Sale Continuous Unrealized Loss Position, Total Aggregate Losses	11,333	742
Obligations of U.S. government sponsored enterprises
Schedule of Available-for-sale Securities [Line Items]
Less than 12 months, Fair Vaule	30,221
Securities Available for Sale, Continuous Unrealized Loss Position, Less Than 12 Months, Aggregate Losses	388
12 months or more, Fair Value	0
Securities Available for Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Losses	0
Total, Fair Value	30,221
Securities Available for Sale Continuous Unrealized Loss Position, Total Aggregate Losses	388
Obligations of the state and political subdivisions
Schedule of Available-for-sale Securities [Line Items]
Less than 12 months, Fair Vaule	17,141	6,434
Securities Available for Sale, Continuous Unrealized Loss Position, Less Than 12 Months, Aggregate Losses	952	122
12 months or more, Fair Value	7,168	3,389
Securities Available for Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Losses	809	356
Total, Fair Value	24,309	9,823
Securities Available for Sale Continuous Unrealized Loss Position, Total Aggregate Losses	1,761	478
Residential mortgage-backed securities
Schedule of Available-for-sale Securities [Line Items]
Less than 12 months, Fair Vaule	159,999	40,471
Securities Available for Sale, Continuous Unrealized Loss Position, Less Than 12 Months, Aggregate Losses	7,338	143
12 months or more, Fair Value	21,437	11,266
Securities Available for Sale, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Losses	1,846	121
Total, Fair Value	181,436	51,737
Securities Available for Sale Continuous Unrealized Loss Position, Total Aggregate Losses	$ 9,184	$ 264