Fair Value - Changes in Level 3 Assets Measured at Fair Value on a Recurring Basis (Details) - Recurring Basis [Member] - Level 3 [Member] - USD ($) $ in Thousands		9 Months Ended
		Sep. 30, 2018	Sep. 30, 2017
MSR [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning Balance		$ 84,269	$ 80,239
Total net (loss) gain included in Mortgage banking, net	[1]	4,857	(10,392)
Additions		12,248	11,630
Sales		0	0
Ending Balance		101,374	81,477
The amount of total gains (losses) for the period included in earnings that are attributable to the change in unrealized gains or losses still held, end of period		13,879	(2,218)
Other Assets - Derivatives [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Beginning Balance		900	1,001
Total net (loss) gain included in Mortgage banking, net	[1]	3,345	3,436
Additions		0	0
Sales		(3,352)	(3,431)
Ending Balance		893	1,006
The amount of total gains (losses) for the period included in earnings that are attributable to the change in unrealized gains or losses still held, end of period		$ 247	$ (1,483)

[1] Total net (loss) gain included in Mortgage banking, net relating to the MSR includes changes in fair value due to market changes and due to run-off.