Debt	3 Months Ended
Mar. 31, 2018
Debt Disclosure [Abstract]
Debt	Debt As of March 31, 2018 and December 31, 2017, AB had $489.8 million and $491.8 million, respectively, in commercial paper outstanding with weighted average interest rates of approximately 2.1% and 1.6%, respectively. The commercial paper is short term in nature, and as such, recorded value is estimated to approximate fair value (and considered a Level 2 security in the fair value hierarchy). Average daily borrowings of commercial paper during the first three months of 2018 and the full year 2017 were $480.5 million and $482.2 million, respectively, with weighted average interest rates of approximately 1.7% and 1.2%, respectively. AB has a $200.0 million, unsecured 364-day senior revolving credit facility (the "Revolver") with a leading international bank and the other lending institutions that may be party thereto, which matures on November 28, 2018. The Revolver is available for AB's and SCB LLC's business purposes, including the provision of additional liquidity to meet funding requirements primarily related to SCB LLC's operations. Both AB and SCB LLC can draw directly under the Revolver and management expects to draw on the Revolver from time to time. AB has agreed to guarantee the obligations of SCB LLC under the Revolver. The Revolver contains affirmative, negative and financial covenants that are identical to those of the Credit Facility. As of March 31, 2018, we had no amounts outstanding under the Revolver. As of December 31, 2017, we had $75.0 million outstanding under the Revolver with an interest rate of 2.4%. Average daily borrowing under the Revolver during the first three months of 2018 and full year 2017 were $21.9 million and $21.4 million, respectively, with weighted average interest rates of approximately 2.4% and 2.0%, respectively.

Debt

As of March 31, 2018 and December 31, 2017, AB had $489.8 million and $491.8 million, respectively, in commercial paper outstanding with weighted average interest rates of approximately 2.1% and 1.6%, respectively. The commercial paper is short term in nature, and as such, recorded value is estimated to approximate fair value (and considered a Level 2 security in the fair value hierarchy). Average daily borrowings of commercial paper during the first three months of 2018 and the full year 2017 were $480.5 million and $482.2 million, respectively, with weighted average interest rates of approximately 1.7% and 1.2%, respectively.

AB has a $200.0 million, unsecured 364-day senior revolving credit facility (the "Revolver") with a leading international bank and the other lending institutions that may be party thereto, which matures on November 28, 2018. The Revolver is available for AB's and SCB LLC's business purposes, including the provision of additional liquidity to meet funding requirements primarily related to SCB LLC's operations. Both AB and SCB LLC can draw directly under the Revolver and management expects to draw on the Revolver from time to time. AB has agreed to guarantee the obligations of SCB LLC under the Revolver. The Revolver contains affirmative, negative and financial covenants that are identical to those of the Credit Facility. As of March 31, 2018, we had no amounts outstanding under the Revolver. As of December 31, 2017, we had $75.0 million outstanding under the Revolver with an interest rate of 2.4%. Average daily borrowing under the Revolver during the first three months of 2018 and full year 2017 were $21.9 million and $21.4 million, respectively, with weighted average interest rates of approximately 2.4% and 2.0%, respectively.