Related Party Transactions - Amounts Due to Parent and Affiliates (Details) - USD ($)		12 Months Ended
		Dec. 31, 2017		Dec. 29, 2017	Dec. 31, 2016		May 19, 2006	Nov. 15, 2004
Related Party Transaction [Line Items]
Due to parent and affiliates		$ 553,901,000			$ 537,990,000
GWL&A Financial
Related Party Transaction [Line Items]
Variable rate basis		three-month London Interbank Offering Rate (“LIBOR”)
Other Related Parties
Related Party Transaction [Line Items]
Due to parent and affiliates		$ 10,560,000			6,898,000
Surplus Notes Payable Due November 2034 | GWL&A Financial
Related Party Transaction [Line Items]
Due to parent and affiliates	[1]	$ 194,532,000			194,502,000
Face amount								$ 195,000,000
Long-term debt, surplus note, interest rate (as a percent)		6.675%
Surplus Notes Payable Due May 2046 | GWL&A Financial
Related Party Transaction [Line Items]
Due to parent and affiliates	[2]	$ 333,400,000			333,400,000
Face amount							$ 333,400,000
Surplus Notes Payable Due May 2046 | GWL&A Financial | After May 16, 2016
Related Party Transaction [Line Items]
Margin added to variable rate basis (as a percent)		2.588%
Surplus Notes Payable Due December 2027 | GWL&A Financial
Related Party Transaction [Line Items]
Due to parent and affiliates		$ 12,000,000	[3]	$ 12,000	0	[3]
Face amount				$ 12,000,000
Long-term debt, surplus note, interest rate (as a percent)				3.50%
Surplus Notes Interest Payable, May 2017 | GWL&A Financial
Related Party Transaction [Line Items]
Due to parent and affiliates		$ 3,409,000			$ 3,190,000

[1] A note payable to GWL&A Financial was issued as a surplus note on November 15, 2004, with a face amount of $195,000 and carrying amounts of $194,532 and $194,502 at December 31, 2017, and 2016, respectively. The surplus note bears interest at the rate of 6.675% per annum, payable in arrears each May and November. The note matures on November 15, 2034.

[2] A note payable to GWL&A Financial was issued as a surplus note on May 19, 2006, with a face amount and carrying amount of $333,400. The surplus note bears an interest rate of 2.588% plus the then-current three-month London Interbank Offering Rate (“LIBOR”). The surplus note became redeemable by the Company at the principal amount plus any accrued and unpaid interest after May 16, 2016. The note matures on May 16, 2046.

[3] A note payable to GWL&A Financial was issued as a surplus note on December 29, 2017, with a face amount and carrying amount of $12,000. The surplus note bears an interest rate of 3.5% per annum. The note matures on December 29, 2027.