Income Taxes (Deferred Tax Assets and Liabilities) (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Components of Deferred Tax Assets
Deferred tax assets - current	$ 0	$ 27,914
Deferred tax liabilities - current	0	(47)
Deferred tax assets - non current	30,039	7,399
Deferred tax liabilities - non current	0	(11,471)
Net operating losses	32,088	24,992
Accrued liabilities	26,355	26,524
Deferred compensation	14,273	12,362
Accrued compensation	6,527	5,920
Deferred revenue	4,564	5,692
Deferred rent	2,469	3,921
Tax credits	4,524	4,670
Equity awards	4,296	5,031
Other, net	1,260	1,746
Valuation allowance	(17,312)	(17,069)
Total deferred tax assets	79,044	73,789
Intangible assets	(40,935)	(44,067)
Capitalized transaction costs	(5,945)	(3,416)
Depreciation	(2,125)	(2,511)
Total deferred tax liabilities	(49,005)	(49,994)
Total net deferred tax assets	$ 30,039	$ 23,795