Debt Securities (Tables)
|
6 Months Ended |
Jun. 30, 2024 |
|---|
| Investments, Debt and Equity Securities [Abstract] |
|
| Investments in Debt Securities, Classified as Available-For-Sale |
Investments in debt securities, classified as available-for-sale, are as follows:
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Amortized |
|
|
Gross unrealized |
|
|
Estimated |
|
(in millions) |
|
cost |
|
|
Gains |
|
|
Losses |
|
|
fair value |
|
June 30, 2024 |
|
|
|
|
|
|
|
|
|
|
|
|
U.S. Treasury bonds |
|
$ |
163.5 |
|
|
$ |
0.1 |
|
|
$ |
(6.1 |
) |
|
$ |
157.5 |
|
Municipal bonds |
|
|
1,382.3 |
|
|
|
5.9 |
|
|
|
(143.2 |
) |
|
|
1,245.0 |
|
Foreign government bonds |
|
|
223.4 |
|
|
|
0.4 |
|
|
|
(10.1 |
) |
|
|
213.7 |
|
Governmental agency bonds |
|
|
213.7 |
|
|
|
— |
|
|
|
(13.9 |
) |
|
|
199.8 |
|
Governmental agency mortgage-backed securities |
|
|
4,315.9 |
|
|
|
1.6 |
|
|
|
(575.4 |
) |
|
|
3,742.1 |
|
U.S. corporate debt securities |
|
|
1,095.7 |
|
|
|
4.0 |
|
|
|
(58.1 |
) |
|
|
1,041.6 |
|
Foreign corporate debt securities |
|
|
498.2 |
|
|
|
3.6 |
|
|
|
(20.8 |
) |
|
|
481.0 |
|
|
|
$ |
7,892.7 |
|
|
$ |
15.6 |
|
|
$ |
(827.6 |
) |
|
$ |
7,080.7 |
|
December 31, 2023 |
|
|
|
|
|
|
|
|
|
|
|
|
U.S. Treasury bonds |
|
$ |
203.3 |
|
|
$ |
0.5 |
|
|
$ |
(4.5 |
) |
|
$ |
199.3 |
|
Municipal bonds |
|
|
1,373.7 |
|
|
|
8.8 |
|
|
|
(136.7 |
) |
|
|
1,245.8 |
|
Foreign government bonds |
|
|
228.4 |
|
|
|
1.4 |
|
|
|
(10.5 |
) |
|
|
219.3 |
|
Governmental agency bonds |
|
|
207.7 |
|
|
|
0.2 |
|
|
|
(12.5 |
) |
|
|
195.4 |
|
Governmental agency mortgage-backed securities |
|
|
4,396.2 |
|
|
|
6.3 |
|
|
|
(526.8 |
) |
|
|
3,875.7 |
|
U.S. corporate debt securities |
|
|
1,007.0 |
|
|
|
6.6 |
|
|
|
(55.2 |
) |
|
|
958.4 |
|
Foreign corporate debt securities |
|
|
478.9 |
|
|
|
5.8 |
|
|
|
(21.1 |
) |
|
|
463.6 |
|
|
|
$ |
7,895.2 |
|
|
$ |
29.6 |
|
|
$ |
(767.3 |
) |
|
$ |
7,157.5 |
|
|
| Gross Unrealized Losses on Investments in Debt Securities |
Investments in debt securities in an unrealized loss position, and their respective length of time in such position, are as follows:
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Less than 12 months |
|
|
12 months or longer |
|
|
Total |
|
(in millions) |
|
Estimated
fair value |
|
|
Unrealized
losses |
|
|
Estimated
fair value |
|
|
Unrealized
losses |
|
|
Estimated
fair value |
|
|
Unrealized
losses |
|
June 30, 2024 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
U.S. Treasury bonds |
|
$ |
94.9 |
|
|
$ |
(1.6 |
) |
|
$ |
55.7 |
|
|
$ |
(4.5 |
) |
|
$ |
150.6 |
|
|
$ |
(6.1 |
) |
Municipal bonds |
|
|
99.3 |
|
|
|
(1.4 |
) |
|
|
1,010.8 |
|
|
|
(141.8 |
) |
|
|
1,110.1 |
|
|
|
(143.2 |
) |
Foreign government bonds |
|
|
57.3 |
|
|
|
(0.1 |
) |
|
|
81.8 |
|
|
|
(10.0 |
) |
|
|
139.1 |
|
|
|
(10.1 |
) |
Governmental agency bonds |
|
|
82.5 |
|
|
|
(0.7 |
) |
|
|
117.3 |
|
|
|
(13.2 |
) |
|
|
199.8 |
|
|
|
(13.9 |
) |
Governmental agency mortgage-backed
securities |
|
|
363.7 |
|
|
|
(3.7 |
) |
|
|
3,283.7 |
|
|
|
(571.7 |
) |
|
|
3,647.4 |
|
|
|
(575.4 |
) |
U.S. corporate debt securities |
|
|
161.3 |
|
|
|
(1.9 |
) |
|
|
587.9 |
|
|
|
(56.2 |
) |
|
|
749.2 |
|
|
|
(58.1 |
) |
Foreign corporate debt securities |
|
|
68.5 |
|
|
|
(0.8 |
) |
|
|
250.2 |
|
|
|
(20.0 |
) |
|
|
318.7 |
|
|
|
(20.8 |
) |
|
|
$ |
927.5 |
|
|
$ |
(10.2 |
) |
|
$ |
5,387.4 |
|
|
$ |
(817.4 |
) |
|
$ |
6,314.9 |
|
|
$ |
(827.6 |
) |
December 31, 2023 |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
U.S. Treasury bonds |
|
$ |
8.2 |
|
|
$ |
(0.1 |
) |
|
$ |
55.4 |
|
|
$ |
(4.4 |
) |
|
$ |
63.6 |
|
|
$ |
(4.5 |
) |
Municipal bonds |
|
|
107.4 |
|
|
|
(0.9 |
) |
|
|
956.8 |
|
|
|
(135.8 |
) |
|
|
1,064.2 |
|
|
|
(136.7 |
) |
Foreign government bonds |
|
|
33.3 |
|
|
|
(0.1 |
) |
|
|
101.4 |
|
|
|
(10.4 |
) |
|
|
134.7 |
|
|
|
(10.5 |
) |
Governmental agency bonds |
|
|
0.4 |
|
|
|
— |
|
|
|
118.9 |
|
|
|
(12.5 |
) |
|
|
119.3 |
|
|
|
(12.5 |
) |
Governmental agency mortgage-backed
securities |
|
|
338.3 |
|
|
|
(6.6 |
) |
|
|
3,225.3 |
|
|
|
(520.2 |
) |
|
|
3,563.6 |
|
|
|
(526.8 |
) |
U.S. corporate debt securities |
|
|
45.1 |
|
|
|
(0.4 |
) |
|
|
602.5 |
|
|
|
(54.8 |
) |
|
|
647.6 |
|
|
|
(55.2 |
) |
Foreign corporate debt securities |
|
|
19.3 |
|
|
|
(0.1 |
) |
|
|
267.3 |
|
|
|
(21.0 |
) |
|
|
286.6 |
|
|
|
(21.1 |
) |
|
|
$ |
552.0 |
|
|
$ |
(8.2 |
) |
|
$ |
5,327.6 |
|
|
$ |
(759.1 |
) |
|
$ |
5,879.6 |
|
|
$ |
(767.3 |
) |
|
| Investments in Debt Securities by Contractual Maturity |
Investments in debt securities at June 30, 2024, by contractual maturities, are as follows:
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
(in millions) |
|
Due in one
year or less |
|
|
Due after
one through
five years |
|
|
Due after
five through
ten years |
|
|
Due after
ten years |
|
|
Total |
|
U.S. Treasury bonds |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Amortized cost |
|
$ |
6.7 |
|
|
$ |
137.0 |
|
|
$ |
4.7 |
|
|
$ |
15.1 |
|
|
$ |
163.5 |
|
Estimated fair value |
|
$ |
6.7 |
|
|
$ |
132.3 |
|
|
$ |
4.7 |
|
|
$ |
13.8 |
|
|
$ |
157.5 |
|
Municipal bonds |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Amortized cost |
|
|
13.1 |
|
|
|
403.4 |
|
|
|
462.0 |
|
|
|
503.8 |
|
|
|
1,382.3 |
|
Estimated fair value |
|
|
12.9 |
|
|
|
370.2 |
|
|
|
393.3 |
|
|
|
468.6 |
|
|
|
1,245.0 |
|
Foreign government bonds |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Amortized cost |
|
|
8.9 |
|
|
|
139.2 |
|
|
|
68.7 |
|
|
|
6.6 |
|
|
|
223.4 |
|
Estimated fair value |
|
|
8.8 |
|
|
|
138.9 |
|
|
|
60.2 |
|
|
|
5.8 |
|
|
|
213.7 |
|
Governmental agency bonds |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Amortized cost |
|
|
36.3 |
|
|
|
130.3 |
|
|
|
1.5 |
|
|
|
45.6 |
|
|
|
213.7 |
|
Estimated fair value |
|
|
35.6 |
|
|
|
126.1 |
|
|
|
1.4 |
|
|
|
36.7 |
|
|
|
199.8 |
|
U.S. corporate debt securities |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Amortized cost |
|
|
18.7 |
|
|
|
723.7 |
|
|
|
272.6 |
|
|
|
80.7 |
|
|
|
1,095.7 |
|
Estimated fair value |
|
|
18.6 |
|
|
|
686.5 |
|
|
|
266.5 |
|
|
|
70.0 |
|
|
|
1,041.6 |
|
Foreign corporate debt securities |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Amortized cost |
|
|
28.7 |
|
|
|
312.5 |
|
|
|
125.0 |
|
|
|
32.0 |
|
|
|
498.2 |
|
Estimated fair value |
|
|
28.2 |
|
|
|
302.5 |
|
|
|
121.9 |
|
|
|
28.4 |
|
|
|
481.0 |
|
Total debt securities (excluding mortgage-backed
securities) |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Amortized cost |
|
$ |
112.4 |
|
|
$ |
1,846.1 |
|
|
$ |
934.5 |
|
|
$ |
683.8 |
|
|
$ |
3,576.8 |
|
Estimated fair value |
|
$ |
110.8 |
|
|
$ |
1,756.5 |
|
|
$ |
848.0 |
|
|
$ |
623.3 |
|
|
$ |
3,338.6 |
|
Total mortgage-backed securities |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Amortized cost |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
4,315.9 |
|
Estimated fair value |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
3,742.1 |
|
Total debt securities |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
Amortized cost |
|
|
|
|
|
|
|
|
|
|
|
|
|
$ |
7,892.7 |
|
Estimated fair value |
|
|
|
|
|
|
|
|
|
|
|
|
|
$ |
7,080.7 |
|
|
| Composition of Debt Securities Portfolio by Credit Rating Agencies |
The composition of the debt securities portfolio at June 30, 2024, by credit rating, is as follows:
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
A- or higher |
|
|
BBB+ to BBB- |
|
|
Non-Investment Grade |
|
|
Total |
|
(dollars in millions) |
|
Estimated
fair value |
|
|
Percentage |
|
|
Estimated
fair value |
|
|
Percentage |
|
|
Estimated
fair value |
|
|
Percentage |
|
|
Estimated
fair value |
|
U.S. Treasury bonds |
|
$ |
157.5 |
|
|
|
100.0 |
% |
|
$ |
— |
|
|
|
— |
% |
|
$ |
— |
|
|
|
— |
% |
|
$ |
157.5 |
|
Municipal bonds |
|
|
1,220.9 |
|
|
|
98.1 |
|
|
|
22.4 |
|
|
|
1.8 |
|
|
|
1.7 |
|
|
|
0.1 |
|
|
|
1,245.0 |
|
Foreign government bonds |
|
|
208.4 |
|
|
|
97.5 |
|
|
|
4.6 |
|
|
|
2.2 |
|
|
|
0.7 |
|
|
|
0.3 |
|
|
|
213.7 |
|
Governmental agency bonds |
|
|
199.8 |
|
|
|
100.0 |
|
|
|
— |
|
|
|
— |
|
|
|
— |
|
|
|
— |
|
|
|
199.8 |
|
Governmental agency mortgage-
backed securities |
|
|
3,742.1 |
|
|
|
100.0 |
|
|
|
— |
|
|
|
— |
|
|
|
— |
|
|
|
— |
|
|
|
3,742.1 |
|
U.S. corporate debt securities |
|
|
494.8 |
|
|
|
47.5 |
|
|
|
386.0 |
|
|
|
37.1 |
|
|
|
160.8 |
|
|
|
15.4 |
|
|
|
1,041.6 |
|
Foreign corporate debt securities |
|
|
250.9 |
|
|
|
52.1 |
|
|
|
190.8 |
|
|
|
39.7 |
|
|
|
39.3 |
|
|
|
8.2 |
|
|
|
481.0 |
|
|
|
$ |
6,274.4 |
|
|
|
88.6 |
% |
|
$ |
603.8 |
|
|
|
8.5 |
% |
|
$ |
202.5 |
|
|
|
2.9 |
% |
|
$ |
7,080.7 |
|
|
| Composition of Debt Securities Portfolio in Unrealized Loss Position by Credit Rating Agencies |
The composition of the debt securities portfolio in an unrealized loss position at June 30, 2024, by credit rating, is as follows:
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
A- or higher |
|
|
BBB+ to BBB- |
|
|
Non-Investment Grade |
|
|
Total |
|
(dollars in millions) |
|
Estimated
fair value |
|
|
Percentage |
|
|
Estimated
fair value |
|
|
Percentage |
|
|
Estimated
fair value |
|
|
Percentage |
|
|
Estimated
fair value |
|
U.S. Treasury bonds |
|
$ |
150.6 |
|
|
|
100.0 |
% |
|
$ |
— |
|
|
|
— |
% |
|
$ |
— |
|
|
|
— |
% |
|
$ |
150.6 |
|
Municipal bonds |
|
|
1,092.5 |
|
|
|
98.4 |
|
|
|
17.3 |
|
|
|
1.6 |
|
|
|
0.3 |
|
|
|
— |
|
|
|
1,110.1 |
|
Foreign government bonds |
|
|
137.2 |
|
|
|
98.6 |
|
|
|
1.2 |
|
|
|
0.9 |
|
|
|
0.7 |
|
|
|
0.5 |
|
|
|
139.1 |
|
Governmental agency bonds |
|
|
199.8 |
|
|
|
100.0 |
|
|
|
— |
|
|
|
— |
|
|
|
— |
|
|
|
— |
|
|
|
199.8 |
|
Governmental agency mortgage-
backed securities |
|
|
3,647.4 |
|
|
|
100.0 |
|
|
|
— |
|
|
|
— |
|
|
|
— |
|
|
|
— |
|
|
|
3,647.4 |
|
U.S. corporate debt securities |
|
|
400.7 |
|
|
|
53.5 |
|
|
|
295.5 |
|
|
|
39.4 |
|
|
|
53.0 |
|
|
|
7.1 |
|
|
|
749.2 |
|
Foreign corporate debt securities |
|
|
184.7 |
|
|
|
58.0 |
|
|
|
117.7 |
|
|
|
36.9 |
|
|
|
16.3 |
|
|
|
5.1 |
|
|
|
318.7 |
|
|
|
$ |
5,812.9 |
|
|
|
92.1 |
% |
|
$ |
431.7 |
|
|
|
6.8 |
% |
|
$ |
70.3 |
|
|
|
1.1 |
% |
|
$ |
6,314.9 |
|
|