CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Statement of Comprehensive Income [Abstract]
Net income	$ 22,974us-gaap_ProfitLoss	$ 16,570us-gaap_ProfitLoss	$ 19,710us-gaap_ProfitLoss
Unrealized gain on marketable securities:
Unrealized holding gain arising during the period	0	0	551
Less income tax (expense)	0	0	(215)
Reclassification adjustment for gains included in net income	0	0	(846)
Less income tax benefit	0	0	330
Interest rate swap	(630)	2,992	(1,789)
Less income tax benefit (expense)	245	(1,164)	696
Foreign currency translation adjustment	(3,160)	292	(74)
Less income tax benefit	190	5	15
Total other comprehensive income (loss)	(3,355)	2,125	(1,332)
Total comprehensive income	$ 19,619	$ 18,695	$ 18,378

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount before tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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Amount of tax expense (benefit), before reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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