Goodwill and other intangibles - Summary of Goodwill (Detail) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Sep. 30, 2015	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Goodwill summary
Beginning balances		$ 251,868	$ 231,838
Acquisitions		7,220	21,440
Purchase adjustments		(5,268)
Impairment	$ (35,900)	(35,749)	0	$ 0
Disposals		(349)	(1,410)
Ending balances		217,722	251,868	231,838
Title
Goodwill summary
Beginning balances		202,002	198,727
Acquisitions		7,220	3,275
Purchase adjustments		0
Impairment		0
Disposals		(349)	0
Ending balances		208,873	202,002	198,727
Mortgage Services
Goodwill summary
Beginning balances		49,866	33,111
Acquisitions		0	18,165
Purchase adjustments		(5,268)
Impairment		(35,749)
Disposals		0	(1,410)
Ending balances		$ 8,849	$ 49,866	$ 33,111

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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-Publisher FASB
-Name Accounting Standards Codification
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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

+ References

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of divestiture of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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