Fair Value Measurements (Assets and Liabilities Measured at Fair Value on a Recurring Basis) (Details) - Recurring - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Assets
Deferred compensation	$ 7,774	$ 7,388
Total assets	7,774	7,388
Liabilities
Contingent consideration	10,840	8,129
Deferred compensation	11,836	11,478
Total liabilities	22,676	19,607
Level 1
Assets
Deferred compensation	7,774	7,388
Total assets	7,774	7,388
Liabilities
Contingent consideration	0	0
Deferred compensation	11,836	11,478
Total liabilities	11,836	11,478
Level 2
Assets
Deferred compensation	0	0
Total assets	0	0
Liabilities
Contingent consideration	0	0
Deferred compensation	0	0
Total liabilities	0	0
Level 3
Assets
Deferred compensation	0	0
Total assets	0	0
Liabilities
Contingent consideration	10,840	8,129
Deferred compensation	0	0
Total liabilities	$ 10,840	$ 8,129