XML 68 R57.htm IDEA: XBRL DOCUMENT v3.10.0.1
Fair Value Measurements - Pricing Sources Used in Pricing Fixed Income Investments (Details)
Sep. 30, 2018
Dec. 31, 2017
Fair Value Disclosures [Abstract]    
Index providers 85.00% 84.00%
Pricing services 13.00% 11.00%
Broker-dealers 2.00% 5.00%
Total 100.00% 100.00%