Business Acquisitions (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
The summary of the allocation of the aggregate fair values of the assets acquired and purchase price for the associate migrations
Goodwill (Note 4)	$ 13,686	$ 13,669	$ 12,946
Associate Migrations [Member]
The summary of the allocation of the aggregate fair values of the assets acquired and purchase price for the associate migrations
Equipment		10
Intangible assets, primarily non-compete agreements		171
Working capital, including work in progress		666
Goodwill (Note 4)		695
Fair value of net assets acquired		1,542
Business Strategy, Inc. [Member]
The summary of the allocation of the aggregate fair values of the assets acquired and purchase price for the associate migrations
Equipment		70
Intangible assets, primarily non-compete agreements		4,041
Working capital, including work in progress		1,967
Deferred tax liabilities		(1,736)
Goodwill (Note 4)		7,577
Fair value of net assets acquired		$ 11,919	$ 11,900