Percentage of voting equity interests acquired at the acquisition date in the business combination.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Amount of revenue from servicing real estate mortgages, credit cards, and other financial assets held by others. Includes premiums received in lieu of regular servicing fees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.13 (d))
-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

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Major Customer (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
Major Customer (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Feb. 07, 2018
Concentration Risk [Line Items]
Loan systems and servicing revenue	$ 55,921	$ 55,950	$ 56,899	$ 54,229	$ 53,764	$ 54,350	$ 54,402	$ 52,330	$ 223,000	$ 214,846	$ 239,858
Concentration Risk Department of Education [Member]
Concentration Risk [Line Items]
Loan systems and servicing revenue									$ 155,800	$ 151,700	$ 133,200
Subsequent Event [Member] \| Great Lakes Educational Loan Services [Member]
Concentration Risk [Line Items]
Percentage of voting interests acquired												100.00%