XML 47 R37.htm IDEA: XBRL DOCUMENT v3.8.0.1
Investments of Insurance Subsidiaries - Additional Information (Detail)
3 Months Ended
Mar. 31, 2018
Investments, Debt and Equity Securities [Abstract]  
Available for sale securities expected maturity of debt securities 4 years 9 months 18 days
Available for sale securities average scheduled maturity 6 years 4 months 24 days