Cash Flows (Narrative) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended		12 Months Ended
	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011	Dec. 31, 2011	Dec. 31, 2010
Cash Flows [Line Items]
Principal amount of promissory note					$ 0
Interest rate		8.625%
Interest income	120		120
Distribution of promissory note including accrued and unpaid interest			17,113
Net receivable	876		876
Increase in accrued employee related costs assumed from Cablevision			7,478
Capital distribution related to benefit accounts			6,602
Unfunded liability in cash balance pension plan	6,193		6,193
Increase in due to affiliates			6,742
Debt distributed to CSC Holdings			1,250,000	1,250,000
Increase in income taxes paid, after utilization of NOLs		7,961
Cablevision Excess Savings Plan [Member]
Cash Flows [Line Items]
Increase in accrued employee related costs assumed from Cablevision			3,616
Cablevision Excess Cash Balance Pension Plan [Member]
Cash Flows [Line Items]
Increase in accrued employee related costs assumed from Cablevision			$ 3,862