v3.19.3
Investments - Summary of Amortized Cost and Estimated Fair Value of Fixed Maturities by Contractual Maturity (Detail) - USD ($)
Sep. 30, 2019
Dec. 31, 2018
Held to maturity    
Due in one year or less, Amortized Cost $ 22,801,000  
Due after one year through five years, Amortized Cost 72,894,000  
Due after five years through ten years, Amortized Cost 179,648,000  
Due after ten years, Amortized Cost 149,371,000  
Mortgage-backed securities, Amortized Cost 34,175,000  
Total held to maturity, Amortized Cost 458,888,742 $ 402,798,518
Available for sale    
Due in one year or less, Amortized Cost 16,975,000  
Due after one year through five years, Amortized Cost 90,226,000  
Due after five years through ten years, Amortized Cost 100,580,000  
Due after ten years, Amortized Cost 15,366,000  
Mortgage-backed securities, Amortized Cost 327,645,000  
Total available for sale, Amortized Cost 550,792,000  
Held to maturity    
Due in one year or less, Estimated Fair Value 22,881,000  
Due after one year through five years, Estimated Fair Value 75,680,000  
Due after five years through ten years, Estimated Fair Value 189,376,000  
Due after ten years, Estimated Fair Value 162,032,000  
Mortgage-backed securities, Estimated Fair Value 34,773,000  
Total held to maturity, Estimated Fair Value 484,742,000 405,038,000
Available for sale    
Due in one year or less, Estimated Fair Value 17,152,000  
Due after one year through five years, Estimated Fair Value 92,564,000  
Due after five years through ten years, Estimated Fair Value 103,705,000  
Due after ten years, Estimated Fair Value 15,971,000  
Mortgage-backed securities, Estimated Fair Value 329,709,000  
Total available for sale, Estimated Fair Value $ 559,101,387 $ 526,558,304