Discontinued Operations - Narrative (Details) - USD ($) $ in Thousands		3 Months Ended			6 Months Ended	9 Months Ended
	Mar. 31, 2016	Sep. 30, 2017	Sep. 30, 2016	Mar. 31, 2016	Mar. 31, 2017	Sep. 30, 2017	Sep. 30, 2016
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from divestiture of business, net of cash divested						$ 0	$ 106,041
Discontinued operations, disposed by sale | Tax lien business | Propel
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Cash consideration	$ 144,400			$ 144,400
Proceeds from divestiture of business, net of cash divested	106,000
Divestiture of cash	$ 38,400
Loss on sale of discontinued operations, net of tax		$ 0	$ 0	$ 3,000	$ 2,000	$ 322	$ 3,000