Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Assets
Cash and cash equivalents	$ 95,065	$ 66,469
Trade accounts receivable, net of allowance for doubtful accounts of $4,477 as of June 30, 2013, and $4,856 as of December 31, 2012	61,919	59,185
Prepaid expenses and other current assets	10,648	6,516
Deferred tax assets	4,911	5,513
Total current assets	172,543	137,683
Equity and other investments	13,934	12,501
Property and equipment, net	58,028	61,669
Goodwill, net	45,461	45,540
Other intangibles, net	6,893	8,177
Noncurrent deferred tax assets	2,473	2,384
Other noncurrent assets	757	1,138
Total assets	300,089	269,092
Liabilities and Stockholders' Equity
Accounts payable	14,700	11,407
Accrued expenses and other current liabilities	24,141	33,879
Deferred revenue	50,996	38,497
Total current liabilities	89,837	83,783
Noncurrent liabilities	29,352	31,900
Total liabilities	119,189	115,683
Stockholders' equity
Preferred stock, $100.00 par value, 750 shares authorized, no shares issued
Common stock, $0.50 par value, 500,000 shares authorized, 32,338 shares issued as of June 30, 2013, and December 31, 2012	16,169	16,169
Retained earnings	183,417	156,530
Common stock held in treasury, 5,416 shares as of June 30, 2013, and 5,714 shares as of December 31, 2012	(2,708)	(2,857)
Accumulated other comprehensive loss	(15,978)	(16,433)
Total stockholders' equity	180,900	153,409
Total liabilities and stockholders' equity	$ 300,089	$ 269,092