The lower of amortized cost or fair value, as of the date of each statement of financial position presented, of servicing assets that are restricted as collateral, and that are reclassified and separately reported in the statement of financial position because the transferee has the right by contract or custom to sell or re-pledge them.

No definition available.

Mortgage Servicing Rights and Mortgage Servicing Liabilities - Activity in MSRs Carried at Lower of Amortize Cost or FV (Details) - Mortgage servicing rights - USD ($) $ in Thousands		3 Months Ended	9 Months Ended
	Jan. 01, 2018	Sep. 30, 2017	Sep. 30, 2017	Dec. 31, 2017	Jun. 30, 2017	Dec. 31, 2016
Amortized cost:
Amortized cost at beginning of quarter	$ 1,583,378	$ 1,384,741	$ 1,206,694
Transfer of mortgage servicing rights resulting from change in method of accounting	(1,583,378)
Balance after reclassification					$ 1,384,741	$ 1,206,694
Mortgage servicing rights resulting from mortgage loan sales		153,061	412,206
Amortization		(48,448)	(129,546)
Amortized cost at end of quarter		1,489,354	1,489,354
Valuation allowance:
Balance at beginning of quarter	(101,800)	(111,583)	(94,947)
Reduction resulting from change in method of accounting	$ 101,800
Balance after reclassification					(111,583)	(94,947)
Application of valuation allowance to write down mortgage servicing rights with other-than-temporary impairment		(17,270)	(33,906)
Balance at end of quarter		(128,853)	(128,853)
Additional disclosures
Mortgage servicing rights, net		1,360,501	1,360,501
Fair value of mortgage servicing rights at beginning of year		1,360,578	1,360,578		1,273,364	1,112,302
Fair value of mortgage servicing rights at end of year		$ 1,360,578	$ 1,360,578		$ 1,273,364	$ 1,112,302
Total				$ 1,467,356