Investment in Securities (Tables)
 12 Months Ended
Dec. 31, 2016
Investment in Securities [Abstract]  
Amortized Cost and Estimated Fair Value for Trading, Available-for-Sale and Held-to-Maturity Securities by Major Security Type and Class of Security
The amortized cost for debt securities and cost for equity securities, gross unrealized gains, gross unrealized losses, and estimated fair value for available-for-sale and held-to-maturity securities by major security type and class of security at December 31, 2016 and 2015, were as follows:

  
2016
 
  
Amortized
Cost
  
Gross
Unrealized
Gains
  
Gross
Unrealized
Losses
  
Estimated
Fair
Value
 
             
Securities available for sale
            
Fixed maturities
            
Obligations of government-sponsored enterprises
 
$
41,442
  
$
87
  
$
(15
)
 
$
41,514
 
U.S. Treasury securities and obligations of U.S. government instrumentalities
  
85,652
   
157
   
(9
)
  
85,800
 
Obligations of the Commonwealth of Puerto Rico and its instrumentalities
  
17,930
   
2,189
   
(68
)
  
20,051
 
Municipal securities
  
650,175
   
34,187
   
(559
)
  
683,803
 
Corporate bonds
  
263,351
   
12,182
   
(661
)
  
274,872
 
Residential mortgage-backed securities
  
684
   
34
   
-
   
718
 
Collateralized mortgage obligations
  
45,069
   
58
   
(242
)
  
44,885
 
Total fixed maturities
  
1,104,303
   
48,894
   
(1,554
)
  
1,151,643
 
Equity securities-Mutual funds
  
240,699
   
30,101
   
(451
)
  
270,349
 
Total
 
$
1,345,002
  
$
78,995
  
$
(2,005
)
 
$
1,421,992
 
 
  
2015
 
  
Amortized
Cost
  
Gross
Unrealized
Gains
  
Gross
Unrealized
Losses
  
Estimated
Fair
Value
 
             
Securities available for sale
            
Fixed maturities
            
Obligations of government-sponsored enterprises
 
$
115,965
  
$
301
  
$
(26
)
 
$
116,240
 
U.S. Treasury securities and obligations of U.S. government instrumentalities
  
163,322
   
234
   
(286
)
  
163,270
 
Obligations of the Commonwealth of Puerto Rico and its instrumentalities
  
25,302
   
317
   
-
   
25,619
 
Municipal securities
  
612,225
   
35,418
   
(197
)
  
647,446
 
Corporate bonds
  
148,198
   
9,782
   
(572
)
  
157,408
 
Residential mortgage-backed securities
  
883
   
54
   
-
   
937
 
Collateralized mortgage obligations
  
22,363
   
368
   
(6
)
  
22,725
 
Total fixed maturities
  
1,088,258
   
46,474
   
(1,087
)
  
1,133,645
 
Equity securities-Mutual funds
  
169,593
   
27,851
   
(373
)
  
197,071
 
Total
 
$
1,257,851
  
$
74,325
  
$
(1,460
)
 
$
1,330,716
 
 
  
2016
 
  
Amortized
Cost
  
Gross
Unrealized
Gains
  
Gross
Unrealized
Losses
  
Estimated
Fair
Value
 
             
Securities held to maturity
            
U.S. Treasury securities and obligations of U.S. government instrumentalties
 
$
619
  
$
158
  
$
-
  
$
777
 
Residential mortgage-backed securities
  
191
   
18
   
-
   
209
 
Certificates of deposits
  
2,026
   
-
   
-
   
2,026
 
  
$
2,836
  
$
176
  
$
-
  
$
3,012
 
 
  
2015
 
  
Amortized
Cost
  
Gross
Unrealized
Gains
  
Gross
Unrealized
Losses
  
Estimated
Fair
Value
 
             
Securities held to maturity
            
U.S. Treasury securities and obligations of U.S. government instrumentalties
 
$
620
  
$
178
  
$
-
  
$
798
 
Residential mortgage-backed securities
  
191
   
17
   
-
   
208
 
Certificates of deposits
  
2,118
   
-
   
-
   
2,118
 
  
$
2,929
  
$
195
  
$
-
  
$
3,124
 
Securities in Continuous Unrealized Loss Position
Gross unrealized losses on investment securities and the estimated fair value of the related securities, aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position as of December 31, 2016 and 2015 were as follows:

  
2016
 
  
Less than 12 months
  
12 months or longer
  
Total
 
  
Estimated
Fair Value
  
Gross
Unrealized
Loss
  
Number of
Securities
  
Estimated
Fair Value
  
Gross
Unrealized
Loss
  
Number of
Securities
  
Estimated
Fair Value
  
Gross
Unrealized
Loss
  
Number of
Securities
 
                            
Securites available for sale
                           
Fixed maturities
                           
Obligations of government-sponsored enterprises
 
$
9,483
  
$
(15
)
  
1
  
$
-
  
$
-
   
-
  
$
9,483
  
$
(15
)
  
1
 
U.S. Treasury securities and obligations of U.S. governmental instrumentalities
  
12,937
   
(9
)
  
1
   
-
   
-
   
-
   
12,937
   
(9
)
  
1
 
Obligations of the Commonwealth of Puerto Rico and its instrumentalities
  
7,758
   
(68
)
  
5
   
-
   
-
   
-
   
7,758
   
(68
)
  
5
 
Municipal securities
  
84,252
   
(559
)
  
13
   
-
   
-
   
-
   
84,252
   
(559
)
  
13
 
Corporate bonds
  
105,054
   
(661
)
  
22
   
-
   
-
   
-
   
105,054
   
(661
)
  
22
 
Collateralized mortgage obligations
  
32,120
   
(239
)
  
8
   
784
   
(3
)
  
1
   
32,904
   
(242
)
  9 
Total fixed maturities
  
251,604
   
(1,551
)
  
50
   
784
   
(3
)
  
1
   
252,388
   
(1,554
)
  
51
 
Equity securities-Mutual funds
  
22,615
   
(451
)
  
4
   
-
   
-
   
-
   
22,615
   
(451
)
  
4
 
Total for securities available for sale
 
$
274,219
  
$
(2,002
)
  
54
  
$
784
  
$
(3
)
  
1
  
$
275,003
  
$
(2,005
)
  
55
 
 
  
2015
 
  
Less than 12 months
  
12 months or longer
  
Total
 
  
Estimated
Fair Value
  
Gross
Unrealized
Loss
  
Number of
Securities
  
Estimated
Fair Value
  
Gross
Unrealized
Loss
  
Number of
Securities
  
Estimated
Fair Value
  
Gross
Unrealized
Loss
     
Number of
Securities
   
                            
Securites available for sale
                           
Fixed maturities
                           
Obligations of government-sponsored enterprises
 
$
18,989
  
$
(26
)
  
1
  
$
-
  
$
-
   
-
  
$
18,989
  
$
(26
)
  
1
 
U.S. Treasury securities and obligations of U.S. governmental instrumentalities
  
130,996
   
(286
)
  
5
   
-
   
-
   
-
   
130,996
   
(286
)
  
5
 
Municipal securities
  
43,937
   
(197
)
  
11
   
-
   
-
   
-
   
43,937
   
(197
)
  
11
 
Corporate bonds
  
35,718
   
(572
)
  
9
   
-
   
-
   
-
   
35,718
   
(572
)
  
9
 
Collateralized mortgage obligations
  
1,448
   
(6
)
  
1
   
-
   
-
   
-
   
1,448
   
(6
)
  
1
 
Total fixed maturities
  
231,088
   
(1,087
)
  
27
   
-
   
-
   
-
   
231,088
   
(1,087
)
  
27
 
Equity securities-Mutual funds
  
9,319
   
(373
)
  
2
   
-
   
-
   
-
   
9,319
   
(373
)
  
2
 
Total for securities available for sale
 
$
240,407
  
$
(1,460
)
  
29
  
$
-
  
$
-
   
-
  
$
240,407
  
$
(1,460
)
  
29
 
Maturities of Investment Securities Classified as Available for Sale and Held to Maturity
Maturities of investment securities classified as available for sale and held to maturity at December 31, 2016 were as follows:

  
Amortized
Cost
  
Estimated
Fair Value
 
       
Securities available for sale
      
Due in one year or less
 
$
11,010
  
$
11,116
 
Due after one year through five years
  
343,904
   
347,140
 
Due after five years through ten years
  
144,748
   
152,225
 
Due after ten years
  
558,888
   
595,559
 
Residential mortgage-backed securities
  
684
   
718
 
Collateralized mortgage obligations
  
45,069
   
44,885
 
  
$
1,104,303
  
$
1,151,643
 
Securities held to maturity
        
Due in one year or less
 
$
2,026
  
$
2,026
 
Due after ten years
  
619
   
777
 
Residential mortgage-backed securities
  
191
   
209
 
  
$
2,836
  
$
3,012
 
Realized Gains and Losses from Investments
Information regarding realized and unrealized gains and losses from investments for the years ended December 31, 2016, 2015, and 2014 is as follows:
 
  
2016
  
2015
  
2014
 
          
Realized gains (losses)
         
Fixed maturity securities
         
Securities available for sale
         
Gross gains from sales
 
$
3,086
  
$
8,208
  
$
5,118
 
Gross losses from sales
  
(2,744
)
  
(646
)
  
(5,884
)
Gross losses from other-than-temporary impairments
  
-
   
(4,267
)
  
(1,170
)
Total fixed maturity securities
  
342
   
3,295
   
(1,936
)
Equity securities
            
Securities available for sale
            
Gross gains from sales
  
19,674
   
17,903
   
20,848
 
Gross losses from sales
  
(1,203
)
  
(1,312
)
  
(2,106
)
Gross losses from other-than-temporary impairments
  
(1,434
)
  
(945
)
  
-
 
Total equity securities
  
17,037
   
15,646
   
18,742
 
Net realized gains on securities available for sale
  
17,379
   
18,941
   
16,806
 
Gross gain from other investment
  
-
   
-
   
1,425
 
Net realized gains on securities
 
$
17,379
  
$
18,941
  
$
18,231
 
Changes in Net Unrealized Gains (Losses)
The other-than-temporary impairments on fixed maturity securities are attributable to credit losses.

  
2016
  
2015
  
2014
 
          
Changes in unrealized gains (losses)
         
Recognized in accumulated other comprehensive income (loss)
         
Fixed maturities – available for sale
  
1,953
   
(25,227
)
  
46,220
 
Equity securities – available for sale
  
2,172
   
(19,479
)
  
(5,620
)
  
$
4,125
  
$
(44,706
)
 
$
40,600
 
Not recognized in the consolidated financial statements
            
Fixed maturities – held to maturity
 
$
(19
)
 
$
(24
)
 
$
49