Credit Facilities and Long-Term Debt - Summary of Outstanding Long-Term Debt Balances (Parenthetical) (Detail)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
LIBOR Plus 1.75 to 2.25%, Bank of America Amortizing Term Loan, Due April 1, 2017 [Member]
Summary of outstanding long-term debt balances
Notes payable, maturity date	Apr. 01, 2017	Apr. 01, 2017
LIBOR Plus 1.75 to 2.25%, Bank of America Amortizing Term Loan, Due April 1, 2017 [Member] | Maximum [Member]
Summary of outstanding long-term debt balances
Changes in interest rate, percentage	2.25%	2.25%
LIBOR Plus 1.75 to 2.25%, Bank of America Amortizing Term Loan, Due April 1, 2017 [Member] | Minimum [Member]
Summary of outstanding long-term debt balances
Changes in interest rate, percentage	1.75%	1.75%
6.16%, Allstate/ CUNA Senior Unsecured Notes, Due June 29, 2017 [Member]
Summary of outstanding long-term debt balances
Notes payable, maturity date	Jun. 29, 2017	Jun. 29, 2017
Changes in interest rate, percentage	6.16%	6.16%
5.38%, Sun Life Fixed Rate Note, Due June 1, 2017 [Member]
Summary of outstanding long-term debt balances
Notes payable, maturity date	Jun. 01, 2017	Jun. 01, 2017
Changes in interest rate, percentage	5.38%	5.38%
LIBOR Plus 3.85%, Sun Life Floating Rate Note, Due May 3, 2014 [Member]
Summary of outstanding long-term debt balances
Notes payable, maturity date	May 03, 2014	May 03, 2014
Changes in interest rate, percentage	3.85%	3.85%
4.15% Sun Life Senior Secured Guaranteed Note, Due June 1, 2017 [Member]
Summary of outstanding long-term debt balances
Notes payable, maturity date	Jun. 01, 2017	Jun. 01, 2017
Changes in interest rate, percentage	4.15%	4.15%