Reverse Mortgages and Related Assets - Summary of Estimated Cash Payments to Reverse Mortgagors (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014
Mortgage Banking [Abstract]
2015	$ 712
2016	576
2017	461
2018	365
2019	285
Years 2020 - 2024	678
Years 2025 - 2029	143
Years 2030 - 2034	21
Thereafter	2
Total	$ 3,243

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