Pension and Postretirement Plans (Narrative) (Details) (USD $)	12 Months Ended																																										12 Months Ended				12 Months Ended
	Dec. 31, 2011		Jan. 02, 2011		Jan. 03, 2010	Jan. 03, 2010 Newsweek [Member] employees	Jan. 03, 2010 Robinson Terminal Warehouse [Member]	Dec. 31, 2011 Pension Plans [Member]	Jan. 02, 2011 Pension Plans [Member]	Jan. 03, 2010 Pension Plans [Member]	Jan. 02, 2011 Pension Plans [Member] Newsweek [Member]	Jan. 03, 2010 Pension Plans [Member] Washington Post Newspaper [Member] employees	Dec. 31, 2011 Pension Plans [Member] Robinson Terminal Warehouse and Washington Post Newspaper [Member]	Dec. 31, 2011 Multiemployer Pension Plans [Member]	Jan. 02, 2011 Multiemployer Pension Plans [Member]	Jan. 03, 2010 Multiemployer Pension Plans [Member]	Dec. 31, 2011 Multiemployer Pension Plans [Member] CWA/ITU Negotiated Pension Plan [Member]	Jan. 02, 2011 Multiemployer Pension Plans [Member] CWA/ITU Negotiated Pension Plan [Member]	Jan. 03, 2010 Multiemployer Pension Plans [Member] CWA/ITU Negotiated Pension Plan [Member]	Dec. 31, 2011 Multiemployer Pension Plans [Member] Other individually insignificant multiemployer pension plans [Member]	Jan. 03, 2010 Multiemployer Pension Plans [Member] Other individually insignificant multiemployer pension plans [Member]	Jan. 02, 2011 Multiemployer Pension Plans [Member] Washington Post Newspaper [Member] CWA/ITU Negotiated Pension Plan [Member]	Dec. 31, 2010 Multiemployer Pension Plans [Member] Washington Post Newspaper [Member] CWA/ITU Negotiated Pension Plan [Member]	Dec. 31, 2009 Multiemployer Pension Plans [Member] Washington Post Newspaper [Member] CWA/ITU Negotiated Pension Plan [Member]	Dec. 31, 2011 Multiemployer Pension Plans [Member] Daily Herald [Member] CWA/ITU Negotiated Pension Plan [Member]	Dec. 31, 2011 Supplemental Executive Retirement Plan (SERP) [Member]	Jan. 02, 2011 Supplemental Executive Retirement Plan (SERP) [Member]	Dec. 31, 2011 Other Postretirement Benefit Plans [Member]	Jan. 02, 2011 Other Postretirement Benefit Plans [Member]	Jan. 03, 2010 Other Postretirement Benefit Plans [Member]	Jan. 03, 2010 Other Postretirement Benefit Plans [Member] Life Insurance Benefits Elimination [Member]	Dec. 31, 2011 Other Postretirement Benefit Plans [Member] Pre-Age 65 [Member]	Dec. 31, 2011 Other Postretirement Benefit Plans [Member] Post-Age 65 MA-PD Plan [Member]	Dec. 31, 2011 Other Postretirement Benefit Plans [Member] Post-Age 65 Non MA-PD Plan [Member]	Jan. 02, 2011 Other Postretirement Benefit Plans [Member] Newsweek [Member]	Jan. 03, 2010 Other Postretirement Benefit Plans [Member] Cable Television [Member]	Dec. 31, 2011 Savings Plan [Member]	Jan. 02, 2011 Savings Plan [Member]	Jan. 03, 2010 Savings Plan [Member]	Dec. 31, 2011 Berkshire Hathaway Class A And Class B [Member]	Dec. 31, 2011 Berkshire Hathaway Class A And Class B [Member] Pension Plans [Member]	Dec. 31, 2010 Berkshire Hathaway Class A And Class B [Member] Pension Plans [Member]	Dec. 31, 2011 Foreign Investments [Member]	Dec. 31, 2011 Single Equity Concentration [Member] Pension Plans [Member] investment	Dec. 31, 2010 Single Equity Concentration [Member] Pension Plans [Member]	Dec. 31, 2011 Concentration In Single Entity, Type Of Industry, Foreign Country Or Individual Fund [Member] Pension Plans [Member]	Dec. 31, 2011 Fixed income securities [Member]	Dec. 31, 2011 Geographic Concentration [Member] Foreign Investments [Member] Pension Plans [Member] country	Dec. 31, 2010 Geographic Concentration [Member] Foreign Investments [Member] Pension Plans [Member]
Retirement Benefits Disclosure [Line Items]
Special termination benefits								$ 0	$ 5,295,000	$ 0	$ 5,300,000
Recognition Of Prior Service Cost Related To Dispositions Including Discontinued Operations								0	2,369,000	0	2,400,000
Employees accepting the Voluntary Retirement Incentive Program						44						221
Early retirement programs expense	634,000		0		64,541,000	6,600,000	1,100,000	634,000	0	64,541,000		56,800,000	600,000
Accumulated benefit obligation								1,191,900,000	1,040,500,000																	86,600,000	72,000,000
Defined Benefit Plan, Contributions by Employer								0	0	0																3,114,000	2,914,000	2,286,000	4,383,000
Estimated employer contributions in next fiscal year								0
Defined benefit plan, target allocation percentage of assets, equity securities, range maximum																																											24.00%
Defined benefit plan, target allocation percentage of assets, singular equity security, without prior approval by plan administrator	10.00%																																							20.00%
Defined benefit plan, target allocation percentage of assets, fixed-income securities, range minimum																																															10.00%
Minimum percentage of plan assets considered as significant concentrations in pension plans																																														10.00%
Value of equity securities investment	303,201,000	[1]	340,910,000	[1]	353,884,000																																				154,000,000	161,600,000
Curtailment gain																												0	(8,583,000)	(8,353,000)	700,000				8,500,000	7,700,000
Discount rate to determine benefit obligation																												3.90%	4.60%
Assumed health care cost trend rate																																8.50%	20.40%	7.50%
Direction of change for assumed health care cost trend rate																																decreasing	decreasing	decreasing
Ultimate health care cost trend rate																																5.00%	5.00%	5.00%
Year that rate reaches ultimate trend rate																																2019	2021	2017
Discount rate to determine periodic cost																												4.60%	5.25%	5.75%
Contributions to multiemployer pension plans														400,000	1,000,000	1,100,000	100,000	600,000		300,000	400,000
Value of investments																																												222,400,000	134,800,000			241,400,000	155,000,000
Equity securities																																												12.00%	8.00%			13.00%	9.00%
Multiemployer pension plan withdrawal charge	2,415,000		20,355,000		0														700,000			20,400,000			2,400,000
Expense associated with the retirement benefits provided under incentive savings plans																																					$ 20,900,000	$ 19,100,000	$ 19,900,000
Number of investments the companys pension plan held which individually exceed 10% of total plan assets																																												1
Number of foreign countries for which the companys pension plan holds investments that exceed 10% of total plan assets																																																1
Percentage of total contribution by the Company																							more than 5%	more than 5%

[1] The Company’s investments in marketable equity securities are classified as available-for-sale.