Debt Instrument, Outstanding Principal

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Extinguishment of Debt Par Value

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Maximum borrowing capacity under the credit facility which can be granted upon request by the entity.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Amount, after accumulated amortization, of debt discount.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 1A
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-Section 55
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-URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Represents the aggregate of total long-term debt, including current maturities and short-term debt.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtLongtermAndShorttermCombinedAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

+ Details

Name:	us-gaap_DeferredFinanceCostsNet
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Balance Type:	credit
Period Type:	duration

- Definition

The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3291-108585

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Including the current and noncurrent portions, carrying value as of the balance sheet date of subordinated debt (with initial maturities beyond one year or beyond the operating cycle if longer). Subordinated debt places a lender in a lien position behind debt having a higher priority of repayment in liquidation of the entity's assets.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section S99
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+ Details

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Balance Type:	credit
Period Type:	instant

- Details

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- Details

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- Details

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DEBT AND OTHER OBLIGATIONS - Summary of Debt and Subordinated Debt Securities (Details) - USD ($)		3 Months Ended
	May 03, 2018	Mar. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Outstanding Principal		$ 983,513,000	$ 991,363,000
Carrying Amounts, Debt		1,083,672,000	1,101,827,000
Carrying Amounts, Subordinated debt securities		605,460,000	605,426,000
Credit Facility
Debt Instrument [Line Items]
Outstanding Principal		0	0
Carrying Amounts, Debt		0	0
Capital lease obligation
Debt Instrument [Line Items]
Outstanding Principal		2,794,000	1,319,000
Carrying Amounts, Debt		2,794,000	1,319,000
Subordinated debt securities
Debt Instrument [Line Items]
Outstanding Principal		610,000,000	610,000,000
Carrying Amounts, Subordinated debt securities		605,460,000	605,426,000
7.375% Senior Notes (2009), due 2019
Debt Instrument [Line Items]
Outstanding Principal		400,000,000	400,000,000
Carrying Amounts, Debt		$ 411,562,000	416,469,000
Stated interest rate (as a percent)		7.375%
8.45% Senior Notes (2009), due 2039
Debt Instrument [Line Items]
Outstanding Principal		$ 180,719,000	190,044,000
Carrying Amounts, Debt		273,713,000	288,547,000
Debt repurchased and subsequently extinguished		14,100,000
Par value of extinguished debt		$ 9,300,000
Stated interest rate (as a percent)		8.45%
Pre-tax gain (loss) on extinguishment of debt		$ 1,100,000
4.30% Senior Notes (2018), due 2028
Debt Instrument [Line Items]
Outstanding Principal		400,000,000	400,000,000
Carrying Amounts, Debt		$ 395,603,000	$ 395,492,000
Stated interest rate (as a percent)		4.30%	4.30%
Debt issued discount, amount			$ 1,000,000
5.35% Subordinated Debentures (2017), due 2052
Debt Instrument [Line Items]
Stated interest rate (as a percent)		5.35%
5.35% Subordinated Debentures (2017), due 2052 \| Subordinated debt securities
Debt Instrument [Line Items]
Outstanding Principal		$ 500,000,000	500,000,000
Carrying Amounts, Subordinated debt securities		495,460,000	495,426,000
Deferred issuance expenses			3,700,000
3.55% Subordinated Funding Obligations (2018), due 2038 (One) \| Subordinated debt securities
Debt Instrument [Line Items]
Outstanding Principal		55,000,000	55,000,000
Carrying Amounts, Subordinated debt securities		$ 55,000,000	55,000,000
Stated interest rate (as a percent)		3.55%
3.55% Subordinated Funding Obligations (2018), due 2038 (Two) \| Subordinated debt securities
Debt Instrument [Line Items]
Outstanding Principal		$ 55,000,000	55,000,000
Carrying Amounts, Subordinated debt securities		$ 55,000,000	$ 55,000,000
Stated interest rate (as a percent)		3.55%
3.55% Subordinated Funding Obligations (2018), due 2038
Debt Instrument [Line Items]
Stated interest rate (as a percent)			3.55%
3.55% Subordinated Funding Obligations (2018), due 2038 \| Subordinated debt securities
Debt Instrument [Line Items]
Outstanding Principal			$ 110,000,000
2015 Credit Facility
Debt Instrument [Line Items]
Line of credit, maximum borrowing capacity	$ 1,000,000,000.0
Line of credit, maximum borrowing capacity to be granted upon entity's request	$ 1,250,000,000.00
Facility fee percentage	0.125%
2015 Credit Facility \| Federal Funds Rate
Debt Instrument [Line Items]
Interest rate added to the base rate (as a percent)	0.50%
2015 Credit Facility \| One-Month LIBOR
Debt Instrument [Line Items]
Interest rate added to the base rate (as a percent)	1.00%
Credit Facility
Debt Instrument [Line Items]
Line of credit, maximum borrowing capacity	$ 1,000,000,000.0
Line of credit, maximum borrowing capacity to be granted upon entity's request	$ 1,500,000,000.0
Facility fee percentage	0.125%
Credit Facility \| Federal Funds Rate
Debt Instrument [Line Items]
Interest rate added to the base rate (as a percent)	0.50%
Credit Facility \| One-Month LIBOR
Debt Instrument [Line Items]
Interest rate added to the base rate (as a percent)	1.00%