- Schedule of Mortgage Servicing Rights at Carrying Value (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Acquired Finite-Lived Intangible Assets
Gross Carrying Amount	$ 129,163	$ 75,412
Accumulated Amortization	(53,006)	(53,251)
Net Carrying Amount	76,157	22,161
Mortgage servicing rights
Acquired Finite-Lived Intangible Assets
Gross Carrying Amount	9,588	7,202
Accumulated Amortization	(3,931)	(3,144)
Net Carrying Amount	$ 5,657	$ 4,058

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Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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