v3.8.0.1

Fair Value of Financial Instruments (Tables) | 9 Months Ended
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Sep. 30, 2017
Fair Value Disclosures [Abstract] |
Fair value hierarchy of financial assets and financial liabilities measured on a recurring basis | At September 30, 2017 and December 31, 2016, we classified our financial instruments measured at fair value on a recurring basis in the following valuation hierarchy:
September 30, 2017 |  | Quoted Prices in Active Markets for Identical Assets (Level 1) |  | Significant Other Observable Inputs (Level 2) |  | Significant Unobservable Inputs (Level 3) |  | Fair Value Based on NAV Practical Expedient |  | Total Fair Value
AFS fixed maturities |  |  |  |  |  |  |  |  |  |
U.S. treasury bonds |  | $ | 5,336 |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | 5,336 |
U.S. agency bonds – mortgage-backed |  | — |  |  | 2,006,402 |  |  | — |  |  | — |  |  | 2,006,402 |
Non-U.S. government and supranational bonds |  | — |  |  | 31,596 |  |  | — |  |  | — |  |  | 31,596 |
Asset-backed securities |  | — |  |  | 262,261 |  |  | — |  |  | — |  |  | 262,261 |
Corporate bonds |  | — |  |  | 1,576,389 |  |  | — |  |  | — |  |  | 1,576,389 |
Municipal bonds |  | — |  |  | 2,603 |  |  | — |  |  | — |  |  | 2,603 |
Other investments |  | — |  |  | — |  |  | 1,500 |  |  | 5,541 |  |  | 7,041 |
Total |  | $ | 5,336 |  |  | $ | 3,879,251 |  |  | $ | 1,500 |  |  | $ | 5,541 |  |  | $ | 3,891,628 |
As a percentage of total assets |  | 0.1 | % |  | 56.7 | % |  | — | % |  | 0.1 | % |  | 56.9 | %
December 31, 2016 |  | Quoted Prices in Active Markets for Identical Assets (Level 1) |  | Significant Other Observable Inputs (Level 2) |  | Significant Unobservable Inputs (Level 3) |  | Fair Value Based on NAV Practical Expedient |  | Total Fair Value
AFS fixed maturities |  |  |  |  |  |  |  |  |  |
U.S. treasury bonds |  | $ | 5,413 |  |  | $ | — |  |  | $ | — |  |  | $ | — |  |  | $ | 5,413 |
U.S. agency bonds – mortgage-backed |  | — |  |  | 1,716,038 |  |  | — |  |  | — |  |  | 1,716,038 |
U.S. agency bonds – other |  | — |  |  | 18,102 |  |  | — |  |  | — |  |  | 18,102 |
Non-U.S. government and supranational bonds |  | — |  |  | 29,934 |  |  | — |  |  | — |  |  | 29,934 |
Asset-backed securities |  | — |  |  | 220,876 |  |  | — |  |  | — |  |  | 220,876 |
Corporate bonds |  | — |  |  | 1,916,205 |  |  | — |  |  | — |  |  | 1,916,205 |
Municipal bonds |  | — |  |  | 65,098 |  |  | — |  |  | — |  |  | 65,098 |
Other investments |  | 6,586 |  |  | — |  |  | 1,000 |  |  | 5,474 |  |  | 13,060 |
Total |  | $ | 11,999 |  |  | $ | 3,966,253 |  |  | $ | 1,000 |  |  | $ | 5,474 |  |  | $ | 3,984,726 |
As a percentage of total assets |  | 0.2 | % |  | 63.4 | % |  | — | % |  | 0.1 | % |  | 63.7 | %
Carrying values and fair values of financial instruments not measured at fair value | The following table presents the fair value and carrying value of the financial instruments not measured at fair value:
|  | September 30, 2017 |  | December 31, 2016
|  | Carrying Value |  | Fair Value |  | Carrying Value |  | Fair Value
Financial Assets |  |  |  |  |  |  |  |
HTM – corporate bonds |  | $ | 1,057,943 |  |  | $ | 1,091,222 |  |  | $ | 752,212 |  |  | $ | 766,135 |
HTM – municipal bonds |  | 60,425 |  |  | 60,884 |  |  | — |  |  | — |
Total financial assets |  | $ | 1,118,368 |  |  | $ | 1,152,106 |  |  | $ | 752,212 |  |  | $ | 766,135 |
Financial Liabilities |  |  |  |  |  |  |  |
Senior Notes - MHLA – 6.625% |  | $ | 110,000 |  |  | $ | 117,040 |  |  | $ | 110,000 |  |  | $ | 111,452 |
Senior Notes - MHNC – 7.75% |  | 152,500 |  |  | 159,600 |  |  | 152,500 |  |  | 164,700 |
Senior Notes - MHNB – 8.00%(1) |  | — |  |  | — |  |  | 100,000 |  |  | 101,600 |
Total financial liabilities |  | $ | 262,500 |  |  | $ | 276,640 |  |  | $ | 362,500 |  |  | $ | 377,752 |
(1) | Please refer to "Note 6. Long-Term Debt", for disclosure regarding the redemption of the 2012 Senior Notes during the second quarter of 2017.

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- Definition Tabular disclosure of assets and liabilities, including [financial] instruments measured at fair value that are classified in stockholders' equity, if any, that are measured at fair value on a recurring basis. The disclosures contemplated herein include the fair value measurements at the reporting date by the level within the fair value hierarchy in which the fair value measurements in their entirety fall, segregating fair value measurements using quoted prices in active markets for identical assets (Level 1), significant other observable inputs (Level 2), and significant unobservable inputs (Level 3). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19190-110258 + Details
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