Derivative Financial Instruments, Effect on Statement of Operations (Details) - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2019	Mar. 31, 2018
Effect of derivative financial instruments on the condensed consolidated financial statements of operations [Abstract]
Gain (Loss) Recognized in Other Comprehensive Income (Loss) (Effective Portion)		$ (912)	$ 684
Cash Flow Hedge Designation [Member]
Effect of derivative financial instruments on the condensed consolidated financial statements of operations [Abstract]
Gain (Loss) Recognized in Other Comprehensive Income (Loss) (Effective Portion)		(912)	684
Gain (Loss) Reclassified from Accumulated Other Comprehensive Loss into Income (Effective Portion)		149	6
Gain (Loss) Recognized in Income	[1]	0	12
Cash Flow Hedge Designation [Member] | Interest-Rate Cap Agreements [Member]
Effect of derivative financial instruments on the condensed consolidated financial statements of operations [Abstract]
Gain (Loss) Recognized in Other Comprehensive Income (Loss) (Effective Portion)		(785)	513
Cash Flow Hedge Designation [Member] | Interest-Rate Cap Agreements [Member] | Interest Expense [Member]
Effect of derivative financial instruments on the condensed consolidated financial statements of operations [Abstract]
Gain (Loss) Reclassified from Accumulated Other Comprehensive Loss into Income (Effective Portion)		118	7
Gain (Loss) Recognized in Income	[1]	0	0
Cash Flow Hedge Designation [Member] | Fixed Income Interest Rate [Member] | Interest Rate Swap [Member]
Effect of derivative financial instruments on the condensed consolidated financial statements of operations [Abstract]
Gain (Loss) Recognized in Other Comprehensive Income (Loss) (Effective Portion)		(127)	171
Cash Flow Hedge Designation [Member] | Fixed Income Interest Rate [Member] | Interest Rate Swap [Member] | Interest Expense [Member]
Effect of derivative financial instruments on the condensed consolidated financial statements of operations [Abstract]
Gain (Loss) Reclassified from Accumulated Other Comprehensive Loss into Income (Effective Portion)		31	(1)
Gain (Loss) Recognized in Income	[1]	0	12
No Hedge Designation [Member]
Effect of derivative financial instruments on the condensed consolidated financial statements of operations [Abstract]
Gain (Loss) Recognized in Income		805	268
No Hedge Designation [Member] | Rate-Lock Mortgage Loan Commitments [Member] | Mortgage Loan Gains [Member]
Effect of derivative financial instruments on the condensed consolidated financial statements of operations [Abstract]
Gain (Loss) Recognized in Income		629	428
No Hedge Designation [Member] | Mandatory Commitments to Sell Mortgage Loans [Member] | Mortgage Loan Gains [Member]
Effect of derivative financial instruments on the condensed consolidated financial statements of operations [Abstract]
Gain (Loss) Recognized in Income		174	(160)
No Hedge Designation [Member] | Purchased Options [Member] | Interest Expense [Member]
Effect of derivative financial instruments on the condensed consolidated financial statements of operations [Abstract]
Gain (Loss) Recognized in Income		86	(93)
No Hedge Designation [Member] | Written Options [Member] | Interest Expense [Member]
Effect of derivative financial instruments on the condensed consolidated financial statements of operations [Abstract]
Gain (Loss) Recognized in Income		(84)	93
No Hedge Designation [Member] | Fixed Income Interest Rate [Member] | Interest Rate Swap [Member] | Interest Income [Member]
Effect of derivative financial instruments on the condensed consolidated financial statements of operations [Abstract]
Gain (Loss) Recognized in Income		(1,147)	1,056
No Hedge Designation [Member] | Variable Income Interest Rate [Member] | Interest Rate Swap [Member] | Interest Income [Member]
Effect of derivative financial instruments on the condensed consolidated financial statements of operations [Abstract]
Gain (Loss) Recognized in Income		$ 1,147	$ (1,056)

[1] For cash flow hedges, this location and amount refers to the ineffective portion.