Condensed Consolidated Statements of Comprehensive Income (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Statement of Comprehensive Income [Abstract]
Net Income	$ 21,800	$ 132,305
Foreign currency translation adjustments:
Translation adjustments arising during the period	(12,088)	746
Adjustment for sale of a business with foreign operations	(41)	0
Total foreign currency translation adjustments, before tax	(12,129)	746
Unrealized (losses) gains on available-for-sale securities:
Unrealized (losses) gains for the period, net	(8,878)	27,738
Reclassification adjustment for realization of (gain) loss on exchange, sale or write-down of available-for-sale securities included in net income	0	785
Total unrealized (losses) gains on available-for-sale securities, before tax	(8,878)	28,523
Pension and other postretirement plans:
Amortization of net prior service cost (credit) included in net income	69	(102)
Amortization of net actuarial loss (gain) included in net income	629	(7,182)
Total pension and other postretirement plans, before tax	698	(7,284)
Cash flow hedge gain	179	172
Other Comprehensive (Loss) Income, Before Tax	(20,130)	22,157
Income tax benefit (expense) related to items of other comprehensive (loss) income	3,202	(8,566)
Other Comprehensive (Loss) Income, Net of Tax	(16,928)	13,591
Comprehensive Income	4,872	145,896
Comprehensive (income) loss attributable to noncontrolling interests	(774)	219
Total Comprehensive Income Attributable to Graham Holdings Company	$ 4,098	$ 146,115