Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Cash flows from operating activities:
Net income	$ 23,756	$ 22,688	$ 17,860
Adjustments to reconcile net income to net cash provided by operating activities:
Gain on reversal of deferred rent liability	0	0	(1,041)
Income tax benefit on reduction of uncertain tax position liabilities	0	(1,602)	(891)
Loss (gain) on change in fair value of contingent consideration, net	(1,676)	789	(517)
Depreciation and amortization	8,617	7,971	6,187
Non-cash compensation expense	3,673	3,615	3,100
Deferred income taxes	(285)	716	147
Changes in other operating items, net of acquired amounts:
Accounts and other receivables	(9,158)	(11,262)	(4,955)
Costs and estimated earnings in excess of billings on uncompleted contracts	(4,941)	(1,256)	(701)
Prepaid expenses and other current assets	(2,807)	(1,227)	(1,599)
Accounts payable and accrued expenses	1,174	4,003	(216)
Billings in excess of costs and estimated earnings on uncompleted contracts	(1,478)	3,218	168
Income tax benefit of stock-based compensation	(359)	(2,034)	(131)
Contingent consideration payments in excess of fair value on acquisition date	(708)	(602)	(721)
Other	445	295	(491)
Net cash provided by operating activities	16,253	25,312	16,199
Cash flows from investing activities:
Additions to property, plant and equipment	(6,714)	(2,536)	(3,975)
Acquisitions, net of cash acquired	(13,505)	(12,184)	(36,077)
Other investing activities	0	0	(157)
Net cash used in investing activities	(20,219)	(14,720)	(40,209)
Cash flows from financing activities:
Short-term borrowings	407	0	0
Contingent consideration payments	(1,026)	(1,263)	(1,238)
Change in negative cash book balance	5,261	(1,888)	1,883
Repurchases of common stock in the open market	(1,747)	(3,433)	(1,414)
Income tax benefit from stock-based compensation	359	2,034	131
Tax withholding payments for employee stock-based compensation in exchange for shares surrendered	(623)	(2,750)	(337)
Proceeds from issuance of common stock	63	284	355
Other financing activities	(6)	(126)	(8)
Net cash provided by (used in) financing activities	2,688	(7,142)	(628)
Effect of exchange rate changes on cash and cash equivalents	(836)	160	(113)
Net change in cash and cash equivalents	(2,114)	3,610	(24,751)
Cash and cash equivalents at beginning of year	7,761	4,151	28,902
Cash and cash equivalents at end of year	5,647	7,761	4,151
Cash paid during the year for:
Interest	179	104	100
Income taxes	13,879	12,532	10,078
Non-cash investing and financing activities:
Accrued contingent consideration	$ 4,243	$ 765	$ 112