CONSOLIDATED STATEMENTS OF STOCKHOLDER'S EQUITY - USD ($) $ in Millions	Total	COMMON STOCK	ACCUMULATED DEFICIT
Increase (Decrease) in Stockholder's Equity
Cumulative net effect of adoption of ASU 2014-09, Revenue from Contracts with Customers, net of $(7), $—, $(50) and $— tax | Accounting Standards Update 2014-09			$ 0
Balance at beginning of period at Dec. 31, 2016		$ 10,050	(1,358)
Increase (Decrease) in Stockholder's Equity
Net income	$ 811		811
Dividends declared to Qwest Services Corporation	(800)		(800)
Dividend of equity interest in limited liability company to Qwest Services Corporation			(12)
Balance at end of period at Sep. 30, 2017	8,691	10,050	(1,359)
Increase (Decrease) in Stockholder's Equity
Cumulative net effect of adoption of ASU 2014-09, Revenue from Contracts with Customers, net of $(7), $—, $(50) and $— tax | Accounting Standards Update 2014-09			0
Balance at beginning of period at Jun. 30, 2017		10,050	(1,424)
Increase (Decrease) in Stockholder's Equity
Net income	265		265
Dividends declared to Qwest Services Corporation			(200)
Dividend of equity interest in limited liability company to Qwest Services Corporation			0
Balance at end of period at Sep. 30, 2017	8,691	10,050	(1,359)
Increase (Decrease) in Stockholder's Equity
Cumulative net effect of adoption of ASU 2014-09, Revenue from Contracts with Customers, net of $(7), $—, $(50) and $— tax | Accounting Standards Update 2014-09			147
Balance at beginning of period at Dec. 31, 2017	9,337	10,050	(713)
Increase (Decrease) in Stockholder's Equity
Net income	1,260		1,260
Dividends declared to Qwest Services Corporation	(925)		(925)
Dividend of equity interest in limited liability company to Qwest Services Corporation			0
Balance at end of period at Sep. 30, 2018	9,819	10,050	(231)
Increase (Decrease) in Stockholder's Equity
Cumulative net effect of adoption of ASU 2014-09, Revenue from Contracts with Customers, net of $(7), $—, $(50) and $— tax | Accounting Standards Update 2014-09			19
Balance at beginning of period at Jun. 30, 2018		10,050	(353)
Increase (Decrease) in Stockholder's Equity
Net income	453		453
Dividends declared to Qwest Services Corporation			(350)
Dividend of equity interest in limited liability company to Qwest Services Corporation			0
Balance at end of period at Sep. 30, 2018	$ 9,819	$ 10,050	$ (231)