Summary of Investments (Investments in Unrealized Loss Position) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015 issue	Dec. 31, 2014 issue
Available-for-sale
Less than 12 months, Number of Issues	133	117
Less than 12 months, Fair Value	$ 198,352	$ 221,670
Less than 12 months, Gross Unrealized Depreciation	2,401	2,660
12 months or longer, Number of Issues	85	195
12 months or longer, Fair Value	150,434	335,951
12 months or longer, Gross Unrealized Depreciation	4,913	11,268
Total, Fair Value	348,786	557,621
Total, Gross Unrealized Depreciation	7,314	13,928
Fixed Maturities [Member]
Available-for-sale
Less than 12 months, Number of Issues	118	105
Less than 12 months, Fair Value	196,975	220,309
Less than 12 months, Gross Unrealized Depreciation	2,160	2,209
12 months or longer, Number of Issues	79	185
12 months or longer, Fair Value	150,126	334,960
12 months or longer, Gross Unrealized Depreciation	4,851	11,160
Total, Fair Value	347,101	555,269
Total, Gross Unrealized Depreciation	7,011	13,369
U.S. Treasury [Member]
Available-for-sale
Less than 12 months, Number of Issues	2	4
Less than 12 months, Fair Value	3,428	2,343
Less than 12 months, Gross Unrealized Depreciation	1	6
12 months or longer, Number of Issues	2	4
12 months or longer, Fair Value	1,663	5,069
12 months or longer, Gross Unrealized Depreciation	5	46
Total, Fair Value	5,091	7,412
Total, Gross Unrealized Depreciation	6	52
U.S. Government Agency [Member]
Available-for-sale
Less than 12 months, Number of Issues	16	11
Less than 12 months, Fair Value	40,258	41,064
Less than 12 months, Gross Unrealized Depreciation	216	70
12 months or longer, Number of Issues	7	35
12 months or longer, Fair Value	22,085	95,198
12 months or longer, Gross Unrealized Depreciation	366	2,352
Total, Fair Value	62,343	136,262
Total, Gross Unrealized Depreciation	582	2,422
States, Municipalities and Political Subdivisions [Member]
Available-for-sale
Less than 12 months, Number of Issues	49	18
Less than 12 months, Fair Value	55,259	30,859
Less than 12 months, Gross Unrealized Depreciation	510	185
12 months or longer, Number of Issues	15	62
12 months or longer, Fair Value	10,927	50,847
12 months or longer, Gross Unrealized Depreciation	212	557
Total, Fair Value	66,186	81,706
Total, Gross Unrealized Depreciation	722	742
Foreign Bonds [Member]
Available-for-sale
Less than 12 months, Number of Issues	6	6
Less than 12 months, Fair Value	13,685	17,158
Less than 12 months, Gross Unrealized Depreciation	468	446
12 months or longer, Number of Issues	0	0
12 months or longer, Fair Value	0	0
12 months or longer, Gross Unrealized Depreciation	0	0
Total, Fair Value	13,685	17,158
Total, Gross Unrealized Depreciation	468	446
Public Utilities [Member]
Available-for-sale
Less than 12 months, Number of Issues	5	10
Less than 12 months, Fair Value	8,581	21,839
Less than 12 months, Gross Unrealized Depreciation	81	194
12 months or longer, Number of Issues	3	4
12 months or longer, Fair Value	2,111	3,611
12 months or longer, Gross Unrealized Depreciation	147	294
Total, Fair Value	10,692	25,450
Total, Gross Unrealized Depreciation	228	488
Corporate Bonds [Member] | Energy [Member]
Available-for-sale
Less than 12 months, Number of Issues	6	8
Less than 12 months, Fair Value	12,156	17,416
Less than 12 months, Gross Unrealized Depreciation	261	420
12 months or longer, Number of Issues	3	3
12 months or longer, Fair Value	7,211	7,061
12 months or longer, Gross Unrealized Depreciation	206	373
Total, Fair Value	19,367	24,477
Total, Gross Unrealized Depreciation	467	793
Corporate Bonds [Member] | Industrials [Member]
Available-for-sale
Less than 12 months, Number of Issues	8	8
Less than 12 months, Fair Value	18,037	17,103
Less than 12 months, Gross Unrealized Depreciation	161	362
12 months or longer, Number of Issues	2	3
12 months or longer, Fair Value	6,536	9,592
12 months or longer, Gross Unrealized Depreciation	1,495	1,792
Total, Fair Value	24,573	26,695
Total, Gross Unrealized Depreciation	1,656	2,154
Corporate Bonds [Member] | Consumer Goods and Services [Member]
Available-for-sale
Less than 12 months, Number of Issues	4	11
Less than 12 months, Fair Value	12,273	28,344
Less than 12 months, Gross Unrealized Depreciation	170	258
12 months or longer, Number of Issues	4	7
12 months or longer, Fair Value	2,517	10,064
12 months or longer, Gross Unrealized Depreciation	5	66
Total, Fair Value	14,790	38,408
Total, Gross Unrealized Depreciation	175	324
Corporate Bonds [Member] | Health Care [Member]
Available-for-sale
Less than 12 months, Number of Issues	2	3
Less than 12 months, Fair Value	7,052	8,244
Less than 12 months, Gross Unrealized Depreciation	4	36
12 months or longer, Number of Issues	2	3
12 months or longer, Fair Value	3,895	7,104
12 months or longer, Gross Unrealized Depreciation	25	174
Total, Fair Value	10,947	15,348
Total, Gross Unrealized Depreciation	29	210
Corporate Bonds [Member] | Technology, Media and Telecommunications [Member]
Available-for-sale
Less than 12 months, Number of Issues	1	4
Less than 12 months, Fair Value	3,194	8,860
Less than 12 months, Gross Unrealized Depreciation	8	68
12 months or longer, Number of Issues	2	4
12 months or longer, Fair Value	9,187	15,742
12 months or longer, Gross Unrealized Depreciation	337	731
Total, Fair Value	12,381	24,602
Total, Gross Unrealized Depreciation	345	799
Corporate Bonds [Member] | Financial Services [Member]
Available-for-sale
Less than 12 months, Number of Issues	1	3
Less than 12 months, Fair Value	2,204	5,908
Less than 12 months, Gross Unrealized Depreciation	1	31
12 months or longer, Number of Issues	0	2
12 months or longer, Fair Value	0	6,131
12 months or longer, Gross Unrealized Depreciation	0	56
Total, Fair Value	2,204	12,039
Total, Gross Unrealized Depreciation	1	87
Mortgage-Backed Securities [Member]
Available-for-sale
Less than 12 months, Number of Issues	4	9
Less than 12 months, Fair Value	168	425
Less than 12 months, Gross Unrealized Depreciation	11	21
12 months or longer, Number of Issues	0	2
12 months or longer, Fair Value	0	1,991
12 months or longer, Gross Unrealized Depreciation	0	25
Total, Fair Value	168	2,416
Total, Gross Unrealized Depreciation	11	46
Collateralized Mortgage Obligations [Member]
Available-for-sale
Less than 12 months, Number of Issues	14	10
Less than 12 months, Fair Value	20,680	20,746
Less than 12 months, Gross Unrealized Depreciation	268	112
12 months or longer, Number of Issues	39	56
12 months or longer, Fair Value	83,994	122,550
12 months or longer, Gross Unrealized Depreciation	2,053	4,694
Total, Fair Value	104,674	143,296
Total, Gross Unrealized Depreciation	2,321	4,806
Equity Securities [Member]
Available-for-sale
Less than 12 months, Number of Issues	15	12
Less than 12 months, Fair Value	1,377	1,361
Less than 12 months, Gross Unrealized Depreciation	241	451
12 months or longer, Number of Issues	6	10
12 months or longer, Fair Value	308	991
12 months or longer, Gross Unrealized Depreciation	62	108
Total, Fair Value	1,685	2,352
Total, Gross Unrealized Depreciation	303	559
Common Stocks [Member] | Public Utilities [Member]
Available-for-sale
Less than 12 months, Number of Issues	3	3
Less than 12 months, Fair Value	246	263
Less than 12 months, Gross Unrealized Depreciation	62	44
12 months or longer, Number of Issues	0	0
12 months or longer, Fair Value	0	0
12 months or longer, Gross Unrealized Depreciation	0	0
Total, Fair Value	246	263
Total, Gross Unrealized Depreciation	62	44
Common Stocks [Member] | Energy [Member]
Available-for-sale
Less than 12 months, Number of Issues	1
Less than 12 months, Fair Value	179
Less than 12 months, Gross Unrealized Depreciation	7
12 months or longer, Number of Issues	0
12 months or longer, Fair Value	0
12 months or longer, Gross Unrealized Depreciation	0
Total, Fair Value	179
Total, Gross Unrealized Depreciation	7
Common Stocks [Member] | Industrials [Member]
Available-for-sale
Less than 12 months, Number of Issues	3	3
Less than 12 months, Fair Value	237	280
Less than 12 months, Gross Unrealized Depreciation	112	70
12 months or longer, Number of Issues	2	2
12 months or longer, Fair Value	63	58
12 months or longer, Gross Unrealized Depreciation	50	54
Total, Fair Value	300	338
Total, Gross Unrealized Depreciation	162	124
Common Stocks [Member] | Consumer Goods and Services [Member]
Available-for-sale
Less than 12 months, Number of Issues	0	1
Less than 12 months, Fair Value	0	129
Less than 12 months, Gross Unrealized Depreciation	0	272
12 months or longer, Number of Issues	2	2
12 months or longer, Fair Value	16	15
12 months or longer, Gross Unrealized Depreciation	1	3
Total, Fair Value	16	144
Total, Gross Unrealized Depreciation	1	275
Common Stocks [Member] | Technology, Media and Telecommunications [Member]
Available-for-sale
Less than 12 months, Number of Issues	7	4
Less than 12 months, Fair Value	521	503
Less than 12 months, Gross Unrealized Depreciation	17	14
12 months or longer, Number of Issues	2	5
12 months or longer, Fair Value	229	218
12 months or longer, Gross Unrealized Depreciation	11	44
Total, Fair Value	750	721
Total, Gross Unrealized Depreciation	28	58
Common Stocks [Member] | Financial Services [Member]
Available-for-sale
Less than 12 months, Number of Issues	1	1
Less than 12 months, Fair Value	194	186
Less than 12 months, Gross Unrealized Depreciation	43	51
12 months or longer, Number of Issues	0	0
12 months or longer, Fair Value	0	0
12 months or longer, Gross Unrealized Depreciation	0	0
Total, Fair Value	194	186
Total, Gross Unrealized Depreciation	43	51
Nonredeemable Preferred Stocks [Member]
Available-for-sale
Less than 12 months, Number of Issues		0
Less than 12 months, Fair Value		0
Less than 12 months, Gross Unrealized Depreciation		0
12 months or longer, Number of Issues		1
12 months or longer, Fair Value		700
12 months or longer, Gross Unrealized Depreciation		7
Total, Fair Value		700
Total, Gross Unrealized Depreciation		$ 7