Accumulated Other Comprehensive Income (Loss) (Schedule of Balances of Accumulated Other Comprehensive Income (Loss)) (Detail) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Accumulated other comprehensive income	[1]					$ 0
Unrealized gains (losses) on available-for-sale securities	[2]	$ 648	$ 0	$ 648	$ (435)
Other Comprehensive Income (Loss), Net of Tax		648	0	648	(2,256)
Unrealized gains (losses) on cash flow hedges	[3]	0	0	0	(1,821)
Net Income (Loss) Attributable to Noncontrolling Interest		0	$ 3	47	$ 3
Accumulated Net Investment Gain (Loss) Attributable to Parent [Member]
Accumulated other comprehensive income		648		648		0
AOCI Attributable to Parent [Member]
Accumulated other comprehensive income		$ 648		648		$ 0
Other Comprehensive Income (Loss), Net of Tax				$ 648

[1] Note 1

[2] Net of tax of $349 and zero for the three months ended September 30, 2017 and 2016, respectively

[3] Net of tax of zero and zero for the three months ended September 30, 2017 and 2016, respectively