Summary of Significant Accounting Policies (Narrative) (Details)	1 Months Ended			12 Months Ended
	Dec. 31, 2023 USD ($) business	Nov. 30, 2022 USD ($)	Mar. 31, 2021 USD ($)	Dec. 31, 2023 USD ($) performanceObligation business	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Feb. 28, 2021
Summary of Significant Accounting Policies [Line Items]
Maximum Term of Contract				1 year
Finance Lease, Right-of-Use Asset | $	$ 22,831,000			$ 22,831,000	$ 13,835,000
Finance Lease, Liability, Current | $	$ 17,357,000			17,357,000	8,697,000
Noncontrolling Interest, Decrease from Redemptions or Purchase of Interests | $				$ 14,965,000	1,200,000	$ 3,508,000
Hoover Treated Wood Products [Member] | Manufacturing [Member]
Summary of Significant Accounting Policies [Line Items]
Noncontrolling Interest, Decrease from Redemptions or Purchase of Interests | $			$ 3,500,000
Graham Holdings Company [Member] | Hoover Treated Wood Products [Member] | Manufacturing [Member]
Summary of Significant Accounting Policies [Line Items]
Noncontrolling Interest, Ownership Percentage by Parent	100.00%			100.00%			98.01%
GHC One [Member] | Group of Senior Managers of GHG [Member]
Summary of Significant Accounting Policies [Line Items]
Percentage of Contributed Capital				5.00%
GHC One [Member] | Graham Holdings Company [Member]
Summary of Significant Accounting Policies [Line Items]
Percentage of Contributed Capital				95.00%
GHC One [Member] | Graham Holdings Company [Member]
Summary of Significant Accounting Policies [Line Items]
Guaranteed Return				8.00%
Percentage of Distributions Available to Common Unit Holders				80.00%
GHC One [Member] | Group of Senior Managers of GHG [Member]
Summary of Significant Accounting Policies [Line Items]
Percentage of Distributions Available to Common Unit Holders				20.00%
GHC One [Member] | GHC One [Member] | Group of Senior Managers of GHG [Member]
Summary of Significant Accounting Policies [Line Items]
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners	5.00%			5.00%
Automotive [Member]
Summary of Significant Accounting Policies [Line Items]
Finance Lease, Right-of-Use Asset | $	$ 10,900,000			$ 10,900,000	5,400,000
Finance Lease, Liability, Current | $	$ 10,900,000			$ 10,900,000	$ 5,400,000
Weiss [Member] | Graham Holdings Company [Member]
Summary of Significant Accounting Policies [Line Items]
Noncontrolling Interest, Ownership Percentage by Parent	50.10%			50.10%
Framebridge [Member] | Graham Holdings Company [Member]
Summary of Significant Accounting Policies [Line Items]
Noncontrolling Interest, Ownership Percentage by Parent	93.40%			93.40%
CSI Pharmacy Holding Company, LLC [Member]
Summary of Significant Accounting Policies [Line Items]
Noncontrolling Interest, Decrease from Redemptions or Purchase of Interests | $	$ 20,000,000	$ 1,200,000
CSI Pharmacy Holding Company, LLC [Member] | Graham Holdings Company [Member]
Summary of Significant Accounting Policies [Line Items]
Noncontrolling Interest, Ownership Percentage by Parent	86.70%			86.70%	76.50%	75.00%
Skin Clique | Graham Holdings Company [Member]
Summary of Significant Accounting Policies [Line Items]
Noncontrolling Interest, Ownership Percentage by Parent	51.00%			51.00%
Transferred over Time [Member]
Summary of Significant Accounting Policies [Line Items]
Percentage of Revenue				54.00%	58.00%	67.00%
Kaplan International [Member]
Summary of Significant Accounting Policies [Line Items]
Number of Performance Obligations				1
Number of business lines | business	1			1
number of performance obligations with variable consideration				2
Higher Education [Member]
Summary of Significant Accounting Policies [Line Items]
Number of Performance Obligations				1
Transition and Operations Support Agreement Initial Term				30 years
Television Broadcasting [Member] | Advertising Revenue [Member]
Summary of Significant Accounting Policies [Line Items]
Number of Performance Obligations				1
Revenue Recognition, Maximum Period between Recognition of Revenue and Receipt of Payment				60 days
Television Broadcasting [Member] | Retransmission Revenue [Member]
Summary of Significant Accounting Policies [Line Items]
Number of Performance Obligations				1
Revenue Recognition, Maximum Period between Recognition of Revenue and Receipt of Payment				60 days
Manufacturing [Member]
Summary of Significant Accounting Policies [Line Items]
Revenue Recognition, Maximum Period between Recognition of Revenue and Receipt of Payment				90 days
Number of business lines | business	4			4
Manufacturing [Member] | Transferred over Time [Member]
Summary of Significant Accounting Policies [Line Items]
Percentage of Revenue				19.00%	21.00%	21.00%
Health Care [Member] | Home Health Revenue [Member]
Summary of Significant Accounting Policies [Line Items]
Number of Performance Obligations				1
Revenue Recognition, Maximum Period between Recognition of Revenue and Receipt of Payment				30 days
Health Care [Member] | Hospice Revenue [Member]
Summary of Significant Accounting Policies [Line Items]
Number of Performance Obligations				1
Revenue Recognition, Maximum Period between Recognition of Revenue and Receipt of Payment				60 days
Health Care [Member] | Other Healthcare Services [Member]
Summary of Significant Accounting Policies [Line Items]
Number of Performance Obligations				1
Automotive [Member]
Summary of Significant Accounting Policies [Line Items]
Number of Performance Obligations				1
Code3 [Member]
Summary of Significant Accounting Policies [Line Items]
Number of Performance Obligations				1
Revenue Recognition, Maximum Period between Recognition of Revenue and Receipt of Payment				100 days
Maximum [Member]
Summary of Significant Accounting Policies [Line Items]
Amortized Intangible Assets, Useful Life (in years)	15 years			15 years
Lessee, Operating Lease, Renewal or Termination Option Term				10 years
Maximum [Member] | Weiss [Member] | Graham Healthcare Group [Member]
Summary of Significant Accounting Policies [Line Items]
Percentage of Shares Eligible to be Redeemed	10.00%			10.00%		10.00%
Maximum [Member] | Framebridge [Member]
Summary of Significant Accounting Policies [Line Items]
Percentage of Shares Eligible to be Redeemed	20.00%			20.00%
Maximum [Member] | CSI Pharmacy Holding Company, LLC [Member] | Graham Healthcare Group [Member]
Summary of Significant Accounting Policies [Line Items]
Percentage of Shares Eligible to be Redeemed	50.00%			50.00%
Maximum [Member] | Machinery and Equipment [Member]
Summary of Significant Accounting Policies [Line Items]
Property, Plant and Equipment, Useful Life (in years)	20 years			20 years
Maximum [Member] | Building [Member]
Summary of Significant Accounting Policies [Line Items]
Property, Plant and Equipment, Useful Life (in years)	50 years			50 years
Minimum [Member]
Summary of Significant Accounting Policies [Line Items]
Lessee, Operating Lease, Renewal or Termination Option Term				1 year
Minimum [Member] | Machinery and Equipment [Member]
Summary of Significant Accounting Policies [Line Items]
Property, Plant and Equipment, Useful Life (in years)	3 years			3 years
Minimum [Member] | Building [Member]
Summary of Significant Accounting Policies [Line Items]
Property, Plant and Equipment, Useful Life (in years)	20 years			20 years