Mortgage Servicing Rights (Tables)

12 Months Ended

Dec. 31, 2016

Summary of MSRs Carried at Fair Value

Following is a summary of MSRs carried at fair value:

		Year ended December 31,
		2016			2015			2014
	(in thousands)
Balance at beginning of year		$	66,584		$	57,358		$	26,452
Purchases			2,739			2,335			—
MSRs resulting from mortgage loan sales			7,337			13,963			47,693
Changes in fair value:
Due to changes in valuation inputs used in    valuation model (1)			(3,210	)		312			(11,455	)
Other changes in fair value (2)			(9,314	)		(7,384	)		(5,193	)
			(12,524	)		(7,072	)		(16,648	)
Sales			—			—			(139	)
Balance at year end		$	64,136		$	66,584		$	57,358
MSRs carried at fair value pledged to secure notes    payable at year end		$	64,136		$	66,584

(1) Principally reflects changes in pricing spread (discount rate) and prepayment speed inputs, primarily due to changes in market interest rates.

(2) Represents changes due to realization of expected cash flows.

Summary of MSRs Carried at Lower of Amortized Cost or Fair Value

Following is a summary of MSRs carried at lower of amortized cost or fair value:

	Year ended December 31,
	2016			2015			2014
	(in thousands)
Amortized cost:
Balance at beginning of year	$	404,101		$	308,137		$	266,697
MSRs resulting from mortgage loan sales		267,755			140,511			73,640
Amortization		(65,647	)		(43,982	)		(31,911	)
Sales		(106	)		(565	)		(289	)
Balance at end of year		606,103			404,101			308,137
Valuation allowance:
Balance at beginning of year		(10,944	)		(7,715	)		(2,577	)
Additions		(2,728	)		(3,229	)		(5,138	)
Balance at end of year		(13,672	)		(10,944	)		(7,715	)
MSRs, net	$	592,431		$	393,157		$	300,422
Fair value at beginning of year	$	424,154		$	322,230		$	289,737
Fair value at year end	$	626,334		$	424,154		$	322,230
MSRs carried at lower of cost or fair value pledged to    secure notes payable at year end	$	592,431		$	393,157

Summary of Company's Estimate of Future Amortization of Existing MSRs Carried at Amortized Cost

The following table summarizes the Company’s estimate of future amortization of its existing MSRs carried at amortized cost. This estimate was developed with the inputs used in the December 31, 2016 valuation of MSRs. The inputs underlying the following estimate will change as market conditions and portfolio composition and behavior change, causing both actual and projected amortization levels to change over time.

	Estimated MSR
Year ended December 31,	amortization
	(in thousands)
2017	$	67,814
2018		63,283
2019		58,297
2020		53,184
2021		48,204
Thereafter		315,321
Total	$	606,103

Mortgage service rights [Member]

Summary of Net Mortgage Loan Servicing Fees Relating to MSRs

Servicing fees relating to MSRs are recorded in Net mortgage loan servicing fees on the Company’s consolidated statements of income and are summarized below:

		Year ended December 31,
		2016		2015		2014
	(in thousands)
Contractually-specified servicing fees		$	125,961	$	97,633	$	76,300
Ancillary and other fees:
Late charges			570		328		—
Other			5,302		4,186		3,708
		$	131,833	$	102,147	$	80,008