Income Taxes Schedule of Deferred Tax Assets and Liabilities (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
Income Tax Contingency [Line Items]
Unbilled receivables	$ 3,560	$ 9,673
Goodwill and other assets	71,979	59,708
Property and equipment	0	2,324
Total deferred tax liabilities	75,539	71,705
Deferred Tax Assets Property and Equipment	(2,753)	0
Deferred Tax Assets, Operating Loss Carryforwards, State and Local	86	138
Capital and state operating loss carryforwards	(86)	(138)
Retirement and other liabilities	(28,823)	(26,220)
Allowance for potentail contract losses and other contract reserves	(3,728)	(3,316)
Total deferred tax assets	(35,390)	(29,674)
Deferred Tax Assets (Liabilities), Net	$ 40,149	$ 42,031