Income Taxes (Tables)

12 Months Ended

Dec. 31, 2016

Income Tax Disclosure [Abstract]

Reconciliations of Statutory U.S. Federal Income Tax Rates to Our Effective Tax Rate for Continuing Operations

Reconciliations of the statutory U.S. federal income tax rates to our effective tax rate for continuing operations follow:

	Years Ended December 31,
	2016		2015		2014
Statutory rate	35.0	%	35.0	%	35.0	%
State tax, net of federal benefit	3.1		3.0		2.9
Impact of state rate change on net deferred tax liabilities, net of federal benefit	(0.5	)	0.5		4.4
State, valuation allowance adjustments on net operating losses	1.0		(0.2	)	(4.0	)
Unrecognized tax benefits, U.S. federal and state, net of federal benefit	1.6		(0.5	)	4.8
Other, net	(0.6	)	(0.3	)	(1.2	)
Effective tax rate	39.6	%	37.5	%	41.9	%

Components of Provision for Income Tax Expense (Benefit)

Income tax expense consists of:

	December 31,
	2016			2015			2014
Current provision:
Federal	$	228,505		$	215,950		$	137,573
State	24,336			26,057			43,282
Total current provision	252,841			242,007			180,855
Deferred (benefit)/provision:
Federal	(89,518		)	(69,546		)	(40,370		)
State	786			(7,681		)	(518		)
Total deferred (benefit)/provision	(88,732		)	(77,227		)	(40,888		)
Provision for income tax expense	$	164,109		$	164,780		$	139,967

Schedule of Deferred Tax Assets and Liabilities

The tax effect of temporary differences that give rise to deferred tax assets and liabilities include the following:

	December 31,
	2016			2015
Deferred tax assets:
Loan reserves	$	72,125		$	45,082
Stock-based compensation plans	16,471			16,939
Deferred revenue	793			209
Operating loss and credit carryovers	8,371			16,106
Unrealized losses	5,364			9,949
Accrued expenses not currently deductible	13,605			10,696
Unrecorded tax benefits	5,702			15,251
Other	10,844			9,871
Total deferred tax assets	133,275			124,103
Deferred tax liabilities:
Gains on repurchased debt	126,403			190,936
Fixed assets	6,831			6,237
Acquired intangible assets	6,288			6,724
Other	2,933			1,794
Total deferred tax liabilities	142,455			205,691
Net deferred tax liabilities	$	(9,180	)	$	(81,588	)

Summary of Changes in Unrecognized Tax Benefits

The following table summarizes changes in unrecognized tax benefits:

	December 31,
	2016			2015			2014
Unrecognized tax benefits at beginning of year	$	47,109		$	59,405		$	7,344
Increases resulting from tax positions taken during a prior period	110,894			3,456			45,184
Decreases resulting from tax positions taken during a prior period	(3,285		)	(10,121		)	—
Increases resulting from tax positions taken during the current period	817			3,447			7,713
Decreases related to settlements with taxing authorities	(123		)	(7,481		)	(236		)
Reductions related to the lapse of statute of limitations	(2,831		)	(1,597		)	(600		)
Unrecognized tax benefits at end of year	$	152,581		$	47,109		$	59,405